So, the way I see it is, Sunset was Celestia's student before Twilight, but Twilight was a filly when she was offered the position as personal student. This would mean that Sunset would have had to have left by this point, but as a filly that wouldn't be likely, so that would make Sunset at least a few years older (say 3-5?) to have been there before Twilight. The hole in this is that when Twilight passes through the mirror, both are the same age.

So ideas? Guesses?

1840503

I'd say she's probably a year or two older. And who knows, the portal messed with the ages of a lot of characters, including the CMC. They're probably the only ones who actually got aged up.

1840503 In the comics that shows Sunset studying with Celestia, Twilight could be seen as a filly in the background, levitating a ball.

1840503
Probably not too much older, but it is hard to judge ages when you got four body forms in regards to age: baby, foal, normal, and really old. Perhaps to explain why Twi was "aged down" is that she is younger than we thought, she's young enough to be confused with high schoolers which could be a reason why Celestia didn't want the rest of the Mane6 to go, they would be too old to blend in.
1840539
Actually I've given some thought about the CMC since I watched the movie, my thoughts is may Canterlot High is part of a K-12 school. The CMC are in the library since there would be no point have three separate libraries if the schools are all together and they went to the dance when they begged their siblings if they could go.

1840503 Well, i guess that kinda depends on how old you think the Mane 6 are in the show. I place them around 18 or 19 at the season 1 opener personally. Now we work backwards. Sunset is seen in the comic as Celestia's student, but it's hard to discern how long she's been there. Since she has her cutie mark (and interpreting from Call of the Cutie that most foals get their mark between about 9 and 11) and from the comments the judges made at her midterm, she's been there a while. So let's assume she's about 17 or so.

Twilight is seen in the background with no cutie mark, levitating a ball, so we know this is after she saw Celestia raise the sun which inspired her to start studying magic, which means it must be close to the time she takes her entry exam, which we'll just assume she takes when she's about 10 or so.

So, before the show, Sunset is 17 and Twilight is about 8 or 9. A pretty big 6 year difference, making Sunset 25 at the show's opening. Then you have the portal to the human world which must screw with your aging, because she came out on the other side as a high school teenager, and she had to have been there longer than 30 moons, because there's no way Twilight's training and 3 seasons of the show happened in 2 and a half years. So, go figure.

1840503

I'm guessing most people assumed Twilight And Sunset Shimmer were of the same age, hence Celestia stating that 'Shimmer had begun her studies around the same time as Twilight.'

However, now we assume that sunset is a little older than Twilight as depicted in the comics.

I prefer to believe that Sunset is a junior in Equestria Girls at the age of seventeen and that she was around fifteen years of age when she came through the portal.

1844870
Not necessary on your last comment, my senior year I was 17 and didn't turn 18 until after or right before I graduated.

I theorize that Sunset Shimmer was twenty years old when she stole the Element of Magic from Twilight Sparkle, though she was physically an eighteen-year-old high school senior while in the human world.

I'm partial to the idea that time passes faster in Equestria than on mirror-Earth. So Sunset spent roughly 3-5 years on Earth but decades passed in Equestria. Which would make her decades before Twilight's time, and that would be why she's never mentioned in the show, and why there's really nothing for her to go back to Equestria to (her parents are long dead).

But what about the portals, you may ask? Twilight spent a few days on Earth in EqG1, but it's not as if months passed in Equestria. Well, when the portal is open, speed of time syncs up between the 2 worlds for a few days.

However, the time differential idea has been debunked by EqG2. A few months has passed on Earth since the Fall Formal, and about as much time has also passed in Equestria (1 TV season).

Forget the IDW comics. I don't count its Easter eggs (Twilight in the bg) as canon even though they got the Sunset story outline and go-ahead from Hasbro. They have a history of putting their own headcanon into the bg as Easter eggs, that later turn out to contradict the show.

1840503

So, the way I see it is, Sunset was Celestia's student before Twilight, but Twilight was a filly when she was offered the position as personal student. This would mean that Sunset would have had to have left by this point,

Why is that? Celestia only said that Sunset became her student "shortly before" she took on Twilight. There wasn't single word to indicate exactly when Sunset abandoned her studies and left through the mirror.

What we do know is that Sunset has been in the human world for at least four years, because she won three Fall Formals in a row and Equestria Girls ends at the eve of the fourth one. I find it unlikely she's been there longer than that since she is supposed to pass for a teenager - if she is about eighteen in EG, then she would be around 14 when she arrived. That seems pretty reasonable to me.

As for how old she is as a pony, I'd say roughly the same age as Twilight, a year or two older at the most. I tend to assume they are both twenty-ish, but the transformation into humans sets them back two or three years.

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1841994

The same comic also depicts Lyra and Minuette as fully grown ponies, which is not possible if Twilight was a foal at that time. Lyra and Minuette were both fillies in Cheese Sandwich's flashback, which puts them in the same age group as the Mane Six.

Since the show canon trumps the comic canon, that at the very least invalidates Twilight's cameo in Sunset's origin story.

1840748

Probably not too much older, but it is hard to judge ages when you got four body forms in regards to age: baby, foal, normal, and really old.

Not quite. Behold Sweetie Belle, age 5:

Interestingly, this is the only example we have of a pony we know the exact canonical age of.

From this we can conclude that Sweetie Belle is at least a fair bit older than five. Since the CMC seem to be meant to be young adolescents (what with the whole coming of age aspect of the cutie marks) this fits well with my headcanon that they are supposed to be around 10-11 or so.

Also, during the Cute Chronicles flashback, Fluttershy was noticably taller and lankier than the other five, which is quite odd since they all have the same body type as adults. I've always taken this to mean that Fluttershy is the oldest of the Mane Six, and had just hit her growth spurt. That would confirm that the CMC are just about to hit puberty.

Once the pony is fully grown, though, it gets really hard to tell how old they are. Twilight's mom is old enough to have a fully grown, married son with a very successful military career, yet she doesn't look a day older than her barely adult daughter.

Apparently ponies age very well.

1841890

So either the portal really can tamper with the age of those who walk though it because Sunset should be too old to go to high school, or that Sunset is somehow using magic to make herself young.

Actually, we do have cause to believe the portal does mess with your age.

See, it's been established that Cheerilee is about the same age as the Mane Six since she and Rarity attended school together. In Equestria Girls, however, the Humane Six are teenage high school students, whereas Cheerilee is a teacher/librarian, which last time I checked requires a university degree, indicating that Cheerilee is considerably older than Rarity and the others. This means that there is no consistency between a pony's age and the age of his or her human counterpart in the mirror world.

Also note that Spike turns into a dog in the mirror world, but other non-pony characters (specifically the diamond dogs) are still human. That seems odd until you realize that your respective species in either world is no more consistent that your age is. In other words, Spike turns into a dog simply because his counterpart happens to be Twilight's pet, not because he's a dragon.

Basically, you turn into whatever the "you" on the other side is, which presumably applies to your age as well. The human versions of Twilight and Sunset are teenagers, thus their pony counterparts become teenagers as well when they cross over because you always transform to match your counterpart perfectly. (Physically, anyway.)

3784703
Any reason to assume the Mane 6 are 20-somethings? They could all be 17 y/o for all we know.
Ponies seem to mature and become adults-with-jobs far younger than humans. Only mandatory education is primary school level.

3784703

Celestia only said that Sunset became her student "shortly before" she took on Twilight.

Celestia's "shortly before" likely has nothing to do with common "shortly before". She is time abyss, for her even a century is not much.

if she is about eighteen in EG, then she would be around 14 when she arrived. That seems pretty reasonable to me.

1) Sirens are ancient history in Equestria, they looked like teenagers in modern Canterlot High.
2) Assuming that what was said in show is true, Granny Smith is centuries years old, making ponies' lifespan much longer than humans'.

3787768

Any reason to assume the Mane 6 are 20-somethings? They could all be 17 y/o for all we know.

Mostly headcanon for me, though it ties in to how old I think Spike is.

Basically, the age of the Mane Six = the age of the CMC + the age of Spike - a year or so given Applejack's claim of being younger than the CMC when getting her cutie mark. I consider Spike to be about the same age as the CMC or slightly older (12-13-ish) since he too is portrayed as an adolescent thematically. So if the CMC are 10 and Spike is 12, the Mane Six would have an average age of 21. As with all headcanon, we simply have to go with what we consider the most likely.

Also, there are 21 candles on Rainbow Dash's birthday cake. Though, that's a bit weird since we only see one side of it. She's presumably not 42, anyway.

3787882

Celestia's "shortly before" likely have nothing to do with common "shortly before". She is time abyss, for her even a century is not much.

That's a rather unfounded assumption. Aside from the fact that we have no actual way of knowing how an immortal being would view time for obvious reasons, we have no reason to suspect Celestia in particular has a different time perspective than her mortal subjects, and we certainly have no reason to believe she would be careless enough to use words like "shortly" in a manner that makes no sense to them. Frankly, I think it would have become a problem for her a ruler if she couldn't even communicate something as simple as what constitutes a long or short period of time.

It's much more reasonable to assume that Celestia meant exactly what Twilight and the Mane Six would have taken it to mean. The fact that Celestia uses that word to begin with is curiously specific and - from a writer's perspective - serves no purpose other than to specify that the time between Sunset and Twilight becoming students was, in fact, relatively brief by normal standards. Insisting otherwise is going out of your way to justify an alternative interpretation.

Anyway, all of that is kinda irrelevant because my point was that Celestia never said anything about when Sunset left. We can only speculate how long Sunset was her student and at what point she aborted her studies because Celestia doesn't really bring that up.

1) Sirens are ancient history in Equestria, they looked like teenagers in modern Canterlot High.

Yes, well, Sunset isn't immortal, is she?

2) Assuming that what was said in show is true, Granny Smith is centuries years old, making ponies' lifespan much longer than humans'.

Regardless of how valid that is, I don't really see your point. I already made it clear that Sunset's age as a pony has nothing to do with her age as a human.

3788224

we have no reason to suspect Celestia in particular has a different time perspective than her mortal subjects,

We does. She sees consequences of her actions a century before. She does see into future with clear understanding that she is likely to see a day a century into future. This certainly changes perspective. So any projections about perception of time onto royal pony sisters are ignorant at best. Meaning that her "recently" must not be believed to be actual "recently" unless proven by other sources.

Regardless of how valid that is, I don't really see your point. I already made it clear that Sunset's age as a pony has nothing to do with her age as a human.

Mmmm. This is very much about how the portal translates age of the passing subject. It may have or not have - currently unclear.

3788224
Okay, your deductions regarding Sunset and the mirror are the best I've seen. I don't like it, but it does seem the most likely canon, so I'm going to have to adjust my upcoming fic somewhat.

(1) Sunset Shimmer left Equestria at most only a few years before Celestia found Twilight. Or she left while Twilight was still young but had started under Celestia.
(2) The mirror changes the user to her counterpart on the destination world.

However, I think that the evidence regarding Spike's age (and consequently the ages of the Mane 6) are more circumstantial. Twilight repeatedly calls Spike a baby. Just as you said with Celestia, we cannot assume that the speaker harbors a hidden meaning behind her words. So Twilight must literally mean that Spike is very young by her perception. Let's say Twilight was 10 y/o when she hatched Spike. She could very well be only 15-16 y/o right now, and Spike only 5-6 y/o. Dragons may simply mature faster.

3789929
So in other words, Sunset is in her early 30's, while Twilight is either late teens or early 20's.......DAYUM!

3790117
Mmmmm....Sunset PI.

3788869

We does. She sees consequences of her actions a century before. She does see into future with clear understanding that she is likely to see a day a century into future. This certainly changes perspective. So any projections about perception of time onto royal pony sisters are ignorant at best. Meaning that her "recently" must not be believed to be actual "recently" unless proven by other sources.

Eh. Like I said, I don't think it's very relevant to the point I was trying to make.

Mmmm. This is very much about how the portal translates age of the passing subject. It may have or not have - currently unclear.

Look, all I'm saying is: When you jump through the portal, you turn whatever age your counterpart on the other side is. That's what makes the most sense to me, anyway, given what we have seen.

3789858

Okay, your deductions regarding Sunset and the mirror are the best I've seen.

It's the Aspergers, really. I get obsessive very easily.

I don't like it, but it does seem the most likely canon, so I'm going to have to adjust my upcoming fic somewhat.

Oh, by all means, write whatever you want to write. I'm not really interested in changing anyone's mind.

Frankly I kinda hate online debates. I prefer to just state my opinion and the move on with my life.

However, I think that the evidence regarding Spike's age (and consequently the ages of the Mane 6) are more circumstantial.

Well, we don't really have anything substantial to go by, so it's all guesswork anyway.

Twilight repeatedly calls Spike a baby. Just as you said with Celestia, we cannot assume that the speaker harbors a hidden meaning behind her words. So Twilight must literally mean that Spike is very young by her perception.

Actually, she calls him a baby dragon. That's very consistent - at no point does she ever refer to him as just a baby.

Me, I interpret it as dragon-specific terminology. Spike is classified a baby by the standards of his species because of how long-lived they are, though I do consider them to mature at a rate comparable to ponies until they reach full adulthood. In the same sense, the "teenage" dragons are actually equivalent to young adult ponies.

Note that while Twilight may refer to Spike as a baby dragon, she doesn't really treat him as an infant. If she really thought of him as a baby, she wouldn't make him do chores, let alone bring him along on potentially dangerous adventures. The context suggests she considers him a child, but a child old enough to handle responsibilities and duties.

Let's say Twilight was 10 y/o when she hatched Spike. She could very well be only 15-16 y/o right now, and Spike only 5-6 y/o.

Like I said, you can go with whatever calculation makes the most sense to you. Though, again, it pretty much has to come out Mane Six = CMC + Spike, more or less.

3790134
3790153
Ooh... that's right. Spike must be either about the same age as Applebloom (within a few months), or slightly younger.

=> Applebloom is older than 5, because we know what a 5 y/o filly looks like. So Spike can't be 5. Applebloom et al are more like 10, or at the very least a few years older than 5.

=> => Which makes Spike approximately 8-10.

=> => => And if Twi hatched Spike at about 8-10, she would be 16-20 at the start of the series.

Princess Celestia: "Sunset Shimmer. A former student of mine. She began her studies with me not long before Twilight."

And if we try to keep Sunset as young as canonically possible... we can say that the IDW comics does offer the best guess. Because if their "internships" were any closer together, and they're both Celestia's prized students and not just run-of-the-mill School For Gifted Unicorns students, Twi should/would have known about Sunset Shimmer if not studied alongside her.

So Sunset would have been about say 15-16 when she left Equestria. After spending 4 years on Earth (which means Twi spent 4-5 years under Celestia's direct tutelage in Canterlot), she'd be 19-20 in Equestrian years. Though her human form would be the age of her counterpart, likely 17-18. Hey! She's going to graduate soon! Where's the TV series gonna take place, college?!

Oh, by all means, write whatever you want to write. I'm not really interested in changing anyone's mind.

No no, I don't subscribe to that. Even if I'm writing an Alt-Univ fanfic, if it veers too far away from canon I think readers would become discouraged. I know I feel that way. It's a slippery slope that eventually begs the question "Why don't you just write an original story?"

Just as the best sci-fi changes only one fundamental thing/concept in a world that is otherwise our own, the best fanfics likewise change only one thing in a setting that is otherwise canon. While we're ever mindful of keeping canon characters in-character, we often neglect the fact that the setting is also a main character.

3790153
3790272

Frankly, the fact that we never seen AJ's parents, even in flashbacks, has always seemed very weird to me. The fact that we don't see them or Apple Bloom in her cutie mark story raises a lot of questions. But I'll get to that in a minute - first let's try to figure out the age difference between the Mane Six and the CMC.

We know that at the time Sweetie Belle was five, Rarity was already an adult. If we go my MLai's hypothesis that the Mane Six are 15-tish at the start of the series and the CMC are 10, then it doesn't add up because Rarity would have been 10 when Sweetie Belle was 5, and she was clearly much older.

I will acknowledge that Sweetie Belle might just remember Rarity as older than she was, but that doesn't seem to be the case given how Sweetie herself is presented in the dream. The context suggests that Luna is showing Sweetie exactly what happened, without subjective memory messing things up.

Now, if we go by my hypothesis and make the Mane Six around twenty instead, Rarity would be fifteen in that dream flashback, so that makes more sense. But that would mean that Apple Bloom either wasn't born or was less than a year old when Applejack left home, which leaves us with the following alternatives:

1: Applejack's parents died immediately after Apple Bloom was born, the same year Applejack decided to move to Manehattan. Meaning AJ decided to leave an already aging Granny and not-yet-adult Macintosh to run a farm and raise an infant while in mourning. I get that she was less responsible back then, but really? This doesn't seem right to me.

2: Applejack can not or will not remember her parents for some reason.

3: The flashback is from the CMC's perspective and Apple Bloom doesn't envision her parents in that context because she can't remember them.

4: Mr and Mrs Apple were alive but absent for other reasons.

5: Amy Pond-style time shenanigans.

So, yeah, either way it's not a perfect theory.

No no, I don't subscribe to that. Even if I'm writing an Alt-Univ fanfic, if it veers too far away from canon I think readers would become discouraged. I know I feel that way. It's a slippery slope that eventually begs the question "Why don't you just write an original story?"

I can respect that, since it's pretty much how I feel about it as well.

3791233
Hmm... More good deductions, Fervidor!

I don't think AB being an infant when AJ left the farm is hard to reconcile. Let's say the parents were alive, but at the time were in the hospital giving birth to AB. Maybe AJ decided to leave at that time due to city-itch plus sibling jealousy. She certainly would leave that part out of the story when telling it to the CMC: "Yeah I ran away because I wished you weren't born, Applebloom."
It doesn't sound like something AJ would've done, but she was 10 y/o so you can't really predict what she would or wouldn't have done. In any case, it can be reconciled any number of ways. So:

(0) Basic assumption: Ponies mature at a similar rate to humans.
(1) The Mane 6 were ~10 y/o during the Cutie Mark Chronicles flashback. They weren't any younger than that because Fluttershy at ~11 y/o was hitting puberty. They weren't any older than that because the rest weren't going into puberty yet. They were slightly younger than the current CMC (except Fluttershy).
(2) The CMC and Spike were newborns/infants during the Cutie Mark Chronicles flashback.
(3) When Sweetie was 5, Rarity looked the same as she does now. So she's at least ~15 y/o. This corroborates with #1 and #2.
(4) At S01E01, the Mane 6 are therefore ~20 y/o. The CMC ~10 y/o.
(5) At EqG1, the Mane 6 are ~21 y/o. It is canon that only 1 year has passed from S01 to S04E01.
(6) Sunset has to be older than Twilight, and left before Twilight became Celestia's personal student. Or very shortly after. Otherwise Twilight would certainly know her.
(7) Twilight became Celestia's "personal protege" at ~10 y/o, which seems like the minimum age before you can apply for the Canterlot School For Gifted Unicorns.
(8) Princess Celestia: "Sunset Shimmer. A former student of mine. She began her studies with me not long before Twilight."
(9) Assuming Sunset became Celestia's protege when she was ~10 y/o, and assuming she studied under Celestia for a few years (as above)... let's say she went to Earth at ~14 y/o, when Twilight was ~10 y/o.
(10) So at EqG1, Sunset is ~25 y/o in pony age...

Wait that doesn't make any sense... Heyyyyy waitasec! Okay, I've found a glaring problem if we assume the Mane 6 to be ~21 y/o. Twilight became Celestia's protege at ~10 y/o. Sunset left Equestria when Twilight was ~10 y/o. At time of EqG1, Twilight is ~21 y/o. That's 11 years! But Sunset was on Earth 4 years!

3791332

That's certainly possible, though note that it means Sunset has spent over ten years in the human world, yet still passes for a high school student.

Assuming I'm right and you take on the age of your counterpart when you travel through the portal regardless of how old you are back home, and that you still age at a normal rate unless you are some kind of immortal being, that means Sunset would have been physically between 8 and 10 years old on arrival, even if she was mentally 14.

Now I'm very confused..............

It seems the only way to reconcile this, would be to say Sunset left Equestria when she was ~21 y/o in pony age.
But that means Twilight was ~17 y/o in pony age at the time.
But that means they both studied under Celestia for ~7 years.
There's no way they don't know each other if that's the case. Celestia is not the type to keep them secret from each other. Especially while telling Twilight to "make some friends already".

3791371

Yeeeah... Honestly, my own headcanon of having them be about the same age kinda relies on ignoring how them not knowing each other makes no damn sense.

Yay, thanks to this thread, I've updated my fanfic's plot so as to accomodate and make sense of the canon, inconsistent as it is. I thought I was at risk of losing an important character, due to the timeline problem. But I managed to overcome it with some clever plotting that nevertheless adhered to Occam's Razor!

It doesn't help figure out the show's canon; it only works with the specific events of my story. Sorry!

Okay, I gotta step in here, since I just rewatched EqG 1 with a friend recently, one who had literally never seen ANYTHING FiM related.

(And yet I started him out with the friggin' movie. Go figure.)

Anyway, assuming that "30 moons' does indeed equate to 2.5 years, then we immediately know one thing: Time moves faster in the human world than Equestria while the portal is closed. Because while I'd have to go back and literally rewatch every episode since the pilot, it seems like every night in Equestria (Discord's shenanigans in season two's two part premiere notwithstanding) has a full moon in it. If we presume this to indeed be the case, then two and a half years on the other side of the mirror is probably akin to something like a month to a month and a half Equestria time. One could account for this by some kind of dimensionally based time-dilation, which I am not scientifically inclined to write out the formulas for. In any case, we have to presume it is true because if the pictures we see of Sunset with those crowns (none of which resemble the Element of Magic, if you'll notice, btw) are all of her winning the Fall formal, and the portal only opens every 2.5 years, then we have to assume she has lived in the human world for nearly 8 years, indicating she would have come to the human world at roughly age 11-12.

Now why do I say 11 to 12? Because of the season one episodes "Griffon the Brush Off" and "The Cutie Mark Chronicles".

If we take Applejack at her word (and being as she is horrendously transparent when trying to lie, we probably should), she was younger than the CMC when she got her mark. In fact, I would put her relatively close to Sweetie's age of five when seen in Luna's dream, since the body types are similar. I bring this up because all of the girls, bar Fluttershy, have the exact same body type when they get their cutie marks. Fluttershy has a different design when she gets hers. However, she has stated canonically in "Griffon the Brush Off" that she is only a year older than Pinkie Pie. If we assume that the other girls are all roughly the same age, that would put them at 6-8 at the absolute oldest when they got their marks. Fluttershy would be 7-9. This means that Twilight would have been around 6 or 7— 8 at the oldest— when she is selected to be Celestia's protege. (This would validate the appearance of Twilight as a filly in the IDW comic, btw.)

If we further posit the idea that Celestia is being literal when she says that Twilight was brought under her tutelage not long after Sunset, then we can assume that she might well have been selected just as Sunset was in fact on the brink of leaving for the human world. If she's only a few years older than Twilight at the time, this puts her at about 9 years old at the most. We've seen that ponies can age remarkably well into later life. (Ponyville was canonically founded by the Apples— specifically Granny Smith and her parents— and Twilight herself claims Ponyville has been around for hundreds of years, indicating that Ponies either age very slowly compared to humans past a certain point, or else their bodies mature far more quickly than their minds, and then their aging either slows or effectively stops at some point for an unspecified period of time at which they begin to age again. Note that in the IDW comic there's what appears to be a photo of Celestia in the Reflections arc taken from early in her reign in Starswirl's old underground home/library, and while she looks exactly the same to the reader, the ponies remark on how young she looks in it.) Cadance is a perfect example in that while she obviously changes her hairstyle when she gets older, she looks almost identical to her teenage self otherwise, as seen in both the season two finale and the two issue story focusing on the backstory of how the two came to be a couple. In fact, she is seen wearing her current hairstyle then as well, meaning her body retains almost the same look altogether. Shining Armor follows a similar pattern, and was clearly a teenager at this time, and was also clearly such in the flashbacks.

At best guess, Shining is in his early to mid-20s at the most, since we know that horses and ponies physically mature much faster than humans in the real world and if this is even partially true in their world, it would place them in a reality in which they physically mature quickly enough to reach a certain point at which their aging either slows or effectively stops for a period of time, but leaves them to chronologically and mentally mature more slowly. Assuming that this is true, it makes sense that Twilight is right around that 6-7 range. Therefore, Sunset leaves Equestria roughly at age 7-9. She then lives through Junior High at CHS (which seems to incorporate Junior High and High School.), based on the changes in the body types of the Humane 5 as seen in the yearbook as compared to their high school appearances. This would put them all on the general cusp of puberty in human physiological terms. 2.5 years per means that she's been in the human world roughly 7 years. This puts her at about 17-18 when she comes back to steal the crown due to having traveled to a world where time was moving considerably slower, allowing Twilight some time to catch up, putting Twilight within 1-2 years of Sunset's age, if not allowing her to catch up completely. As a result, Twilight is within the general age range of 16-17, unless we assume that her knowledge pool is enough that she could have had another year to study before the portal opened, putting her comfortably at around 17 and a half, putting her within six months of Sunset's age at the youngest. Again, this assumes the CHS world isn't moving even more slowly timewise and allowing her to match Sunset's age exactly.

Now I know someone's gonna bring up the birthday cake in Pinkie's Pride. But here's the kicker. It wasn't just a birthday cake. It was also an anniversary cake, since according to Rainbow Dash, she's lived in Ponyville for some time now, and apparently moved there on her birthday, according to her own word on the subject. Keeping this in mind, those candles are a combination of her age and how many years she's lived in Ponyville. If we assume that to be true, we can say that 21 candles is closer to her real age since if she's only lived in Ponyville for a few years, and if as we have established Twilight and indeed most of the girls are around the same rough age, that means Rainbow is likely around that same 17-18 years of age, and has likely lived in Ponyville for at least five or six years. Any candles we didn't see, assuming any exist, are likely to be part of this combination of actual years she's lived in Ponyville with her chronological age. So if she moved to Ponyville within 7 years— and bear in mind we know that Applejack, at roughly 5-7 years of age went off to Manehattan alone and came back to Ponyville alone, so apparently some level of autonomy can be granted or taken within a few years of age if they want— then we can deduce that Rainbow has been living in Ponyville since the age of about 12 at the oldest. Remember, Fluttershy is at least a year older than the rest of the girls, if they are indeed all the same age as Pinkie was when they all got their marks.

So...yeah, that all taken together, Sunset would be roughly 19 by the time she graduates from CHS at some point, assuming that the above is all true. Again, this theory sort of demands that the photos we see in EqG 1 are all of the past times she's won the Fall Formal, and not shots of her winning the Fall Formal and the Spring Fling, which would skewer this entire theory. However, given that they only mention her winning of the Fall Formal when showing those three photographs, I'm pretty sure this would hold up.

3815913
2 flaws in your premise invalidating the rest of your wall o' logic:
>> The moon was crescent in 2 instances of the show.
>> Fall Formal happens once per year. How did you get the notion that it's every 2.5 years? And therefore b/c she won 3 FF's, she's been at the school 7.5 years??? That makes no sense.

3824541

Interesting points, and I do have an answer, one that could partially revise my original theory:

1. I did bring up that there is a different look to the moon during Discord's first appearance. So that's one instance of crescent moon. Which was the other?

2. I'm projecting 7 years based on a few factors:

a) if the IDW comic is to be believed, Sunset was roughly similar in age to filly Twilight. As such, when she came through the portal, she would have been in Jr. High at the most when she enrolled in the human school. This makes the most sense since if you look at the yearbook in EqG, AJ claims that it was taken during Freshman year. However they look far younger then freshmen in a high school. This could be explained away as them not yet having shed their baby fat (as their faces, if nothing else, are far more pudgy than even the CMC's human counterparts.), or else that she meant that it was taken going into Freshman year, meaning it was taken during Jr. High. That being the case, she would have lived at least 2 and a half years in the human world, winning her first Fall Formal either at some point during that first 2.5 years. She has won the crown twice since that time, if those photos are all of the Fall Formal (as stated in my previous post), then she has lived there for at least five years, give or take. Again, remember that in my theory we're assuming that the idea that portal opens every 30 moons, means 30 moons on the side the mirror lets out to. That leads to a revision of my original idea. As I said before, I believe she lived through Junior High in the human world, since as we know, movie/series canon trumps comic book canon, which shows the girls meeting at a time when they looked closer to how they normally do within the film as opposed to what they looked like in the yearbook picture. What I did not make clear in my previous post was how long I believed she has spent in Jr. high. If we take into account the ages I originally posited earlier, then she lived at least 2-3 years in the Jr. high section of the school. This accounts for the first few years. If we assume this to be the case, then she has lived at least an overall time of something like 6 years by the time the portal is getting ready to open again. As such, she has lived close to 7 years in the human world, taking these new points of my theory into account. Or else one could simply conclude that as of Rainbow Rocks, she's in her 7-8th year in the human world altogether.

3824650
(1) This is the usual depiction of the moon in MLP. There are other instances in the series, but they all look like this:

The shadow of their moon is never as dark as it is with our moon. This means the MLP moon is never full. Rather, it's always this lit-crescent. You can see it's also this lit-crescent in S01E01, when Nightmare Moon was escaping from it.

But anyways, that's not the fault of your logic. The fault is you think time passes faster in Equestria. That was the common fan conjecture during EqG1 movie, but now with EqG2 movie we see that's not the case. A couple of months passed on Earth from EqG1 to EqG2, but the approx the same amount of time has passed in Equestria from beginning of season 04 to the end of season 04. We know this because we know S01-S03 took place in 1 year, so for MLP each TV season does not equal 1 real year.

Also, if we go by your conjecture, then "30 moons" means 30 months on Earth but 30 days in Equestria. This would actually mean that time passes faster on Earth. (But this flaw doesn't even matter because the time differential conjecture is invalid to start with.)

(2) AJ clearly meant that the photo was taken early in HS freshman year. Trying to judge their age via their faces is deceptive; instead, look at their bodies. Their younger selves look similar to the human CMC in body shape and size. But that's not relevant to Sunset's age.

Sunset has been on Earth for a total of 5 years as of EqG1 (meaning she came to Earth 2 portal rotations ago), in order to have won 3 FF crowns as of EqG1.

I can guess she's was probably a young teen compared to filly twilight shortly before she left Celestia, so nowadays, i say about 18 years of age

3845410 that there is a parody, dat haz nuffing 2 do wiff the EG UNIVERSE you rufflekopter!

Same thing as stars and stripes beats hammer and sickle, look it up!

I've just pegged her as two and a half years older than Twilight and left it at that.

What? I'm a fan of Occam's Razor.

3791332
3791349
Actually, since the entire season 4 happened inbetween EQG 1 and 2, but it would be strange for more than a week to pass from Adogio seeing Sunset banished to the Sirens enrolling at CHS, we can conclude that Time progresses much faster in Equestria. Sunset might easily be gone from Equestria for a decade, while only two years happened in the human world.

4120556

Actually, since the entire season 4 happened inbetween EQG 1 and 2, but it would be strange for more than a week to pass from Adogio seeing Sunset banished to the Sirens enrolling at CHS, we can conclude that Time progresses much faster in Equestria.

Or, you know, they spent the time preparing, collecting rumors and information about what actually happened, finding out exactly which students had Equestrian magic and why, and probably just waiting for an ideal opportunity to come around where they could make the best use of their abilities. Like say a musical showcase.

They're immortals, so they are probably pretty patient. Note that they didn't just show up and start making stuff up as they went along - they had that shit planned out. The average heist movie crew runs into more unforeseen problems than they did.

Sunset might easily be gone from Equestria for a decade, while only two years happened in the human world.

Except that was never referenced at all, which it really, really should have been if that was the case. Celestia and Luna would have been damned sure to tell Twilight that, oh by the way, time runs five times faster in the other world, because that is pretty important information.

4120556
I would like nothing better than there being a time differential between Earth and Equestria, but the evidence doesn't support it even circumstantially.

The most logical answer is that Sunset has been on Earth for ~10 years, and is at least 25-26 y/o but is in a human form that appears 18 y/o. I don't like that, and I don't think the writers really thought it through while writing EqG1, but that's what makes the most sense.

4120594 Really? They need several month of planing ahead and yet they don't really seem that prepared when they arrive. Shouldn't they know about the showcase in that case? Or the human Mane six being responsible for the magic? Or Twilight?

Sunset is most likely 17 because in eqg1 the pictures of her winning the fall formal add up to three so she's been in high school for 3 years and this is her fourth time running so she's a senior so she'd most likely be 17

4120594

Or, you know, they spent the time preparing

thanks!! you saved me from getting an aneurism after trying to add another inconsistency to the pile...

but still, it's a complete mess!!! we have several facts that don't fit all together (I'm mostly putting together the bulk of what you people have said):

1. The age of Spike and the CMC: both The Cutie Mark Chronicles and For Whom the Sweetie Belle Toils support them being about the same age, between 10 and 12

2. The age at which Twilight started studying directly under Celestia: we can safely assume that it was around 9-10, almost immediately after getting her Cutie Mark (Celestia wouldn't want to leave such a powerful unicorn unsupervised), and that the Mane 6 are between 19 and 24 (adding the potential ages for the CMC and Spike, from number 1) by the time season 1 starts

3. The ages Sunset and Twilight had when the former left for the human world: this is where it gets tricky. The IDW comic makes it look like Sunset was Celestia's only apprentice at the time (even if we ignore Twily's little cameo), and that's the only clue as to how the events transpired (even Celestia's explanation in EqG was at best, vague), and I say clue, because even that version of the story still has some holes in it (like the aformentioned cameo). Thus, the earliest age at which Sunset could have escaped is 14-16, if we are to believe she left being a full grown mare (like Rarity when Sweetie Belle was 5). But, if Sunset was actually Celestia's only apprentice at the time, it means that this must've happened at least 10 years prior to the events of EqG (9 years minimum before season 1 plus 1 year until EqG), making Sunset at least 5 years older than Twilight... but is it like that? In order for Sunset's age to fit with numerals 1 and 2, we have to make changes to the logic, and thus we have 3 options: first, we could believe that Sunset is 5 years older than Twilight and thus, believe she's been in the human world for about 10 years prior to EqG; second, we could believe that Celestia was grooming two proteges separately, in secret from each other (doesn't make much sense, being that she wanted both to make friends); or third, we adjust the age at which Twilight started as Celestia's personal student, for Sunset to be living only 4-5 years in the human world, very likely cutting the age difference with Twilight, and leaving them at almost the same age (Sunset being probably 1-2 years older)

4. Sunset's apparent age in the human world: here, there are few arguments, and I'm inclined to agree with Fervidor's theory of beings taking on the physical appearance of their counterparts from the other world (therefore implying there IS a human Sunset Shimmer somewhere in that world), even if we still need to see a human go through the mirror to Equestria in order to confirm said theory. With this, no matter how numeral 3 can be explained, it makes sense that Sunset is a senior year high schooler by the time of the first movie, since she took on the form of her human counterpart, but how young did she look when she arrived? This again depends on numeral 3, for if Sunset spent 10+ years in the human world (if numerals 1 and 2 stay true), that means she left being 14 minimum, but arrived to a 7-8 year-old body... quite a shock, IMO. If the take the third option in numeral 3, that means that Sunset would've left being around 16-17, to arrive into a 14-15 year-old body... less of a shock, but it kind of makes sense for her to have won the Fall Formal 3 years in a row, prior to EqG

With all of these points, we have 2 choices: we either believe Sunset spent 10+ years in the human world, or we believe that Twilight didn't immediately start studying privately under Celestia (I seriously doubt Celestia being the type to keep the secret of another protege), and thus, with Sunset's escape, Celestia decided to focus on the filly with the amazing raw power... taking both options into account, we can estimate Sunset Shimmer's actual age at the time of the Friendship Games to be between 21 and 27 years old. So, at best, and even if numeral 4 proves false, Sunset is just a little older than the average high schooler, so it'd make sense that she still can pass for a teenager in the human world.

Numeral 3 is the one that spurs the most debate, but I hope that this convulsive pile of brainstorming has condensed most of the discussion here

4947447
4947533
"Thread necromancy" would be when someone posts in an old, dead thread and has nothing of value to add to the conversation.

This is clearly not the case here. Just because there has been several weeks since the last post does not forever lock this conversation away from happening again. Indeed, we would much rather this be done than start a new thread.

4947274
Thank you for posting here instead of starting a new, redundant thread.

4947997 Can't even let us make a joke huh? Alrighty then.

4947997 no problem! I was just taking a look at the Shimmer Nexus and found this post interesting enough to read the whole conversation carefully... then I decided that bringing the conclusions together for future reference (to be compared with future information) would be useful for those who come take a look, as well as for me to make sense of the whole mess in my head

besides, very few of the posts on this thread mentioned a final veredict on what was the most likely age for Sunset, given the current info (damn, I'm going full Twilight on this, no wonder I love Sunny )

4948007
So let me get this straight, what you're proposing is:

(1) Twilight hatched Spike at 10 y/o, and Celestia said "I will make you my personal student."
(2) But offscreen, Celestia told the Sparkle family, "Well, Twilight is too young atm. I will start her apprenticeship when she's ~15."
(2a) We have new S05 evidence for this, because in "Amending Fences" Twi did spend some time in the School For Gifted Unicorns. She didn't jump from hatching Spike to immediately becoming Celestia's personal student.
(3) Meanwhile, Celestia is training Sunset, who is only a couple of years older than Twi.
(4) Sunset runs away. At this point, Twi is ~15 y/o. Celestia starts Twi's apprenticeship.
(5) Sunset de-ages a couple of years when transformed into a human, but it's not a drastic number of years.
(6) ~5 years later, EQG1 happens.

4948640 yes, most of that is precisely what I intended to say ... but, I checked the flashbacks on Amending Fences while I was writing my conclusions, and neither Twilight or Moondancer have their Cutie Marks on the flashbacks regarding their time at school, all of them are blank flanks, for that matter

So, it seems that, even if we assume that Twilight kept studying with Moondancer and spending some time with her friends after hatching Spike and before she became Celestia's protégée (by taking into account that those 6 were still friends even when Twilight was completely focused on her studies under Celestia), there's still no conclusive evidence that can prove soundly that my theory of Twilight starting her studies under Celestia until ~15 is 100% accurate... if anything, it's the only way the timeline makes some sense

4948640

2a) We have new S05 evidence for this, because in "Amending Fences" Twi did spend some time in the School For Gifted Unicorns. She didn't jump from hatching Spike to immediately becoming Celestia's personal student.

This is no evidence, being Celestia's student does not exclude her being also a student at the School, and Celestia probably doesn't have time to teach basic algebra, her being Celestia's student is probably extra curricular activities in addition to whatever she does at School.

(3) Meanwhile, Celestia is training Sunset, who is only a couple of years older than Twi.
(4) Sunset runs away. At this point, Twi is ~15 y/o. Celestia starts Twi's apprenticeship.

Not if we go by the comics, in the comics Twilight is still a blank flank being foal sat by Cadance when Sunset leaves already a full grown mare, a young one surely, but full grown non the less.

(5) Sunset de-ages a couple of years when transformed into a human, but it's not a drastic number of years.

The ages in Humania don't really mean anything, we only get glimpses and they are always off by a random margins to random characters:

1) Cheerilee is about the same age as Rarity in the show, both being in the same class in Cutie Mark Chronicles, yet she is like a middle aged teacher in EqG, she's the closest to keeping her Equestria age and she's still probably older than in Equestria.

2) Applejack is probably older than the other Mane 6 given that she was apparently done with school and old enough to go live by herself, apparently not in Rarity's class, yet she was still in the same grade as the others.

3) Pinkie is a year younger than Fluttershy, yet they are also both in the same year.

4) The CMC are at the most 2 years younger than the Mane 6 in EqG, since they are all in High School at the same time, yet Rarity was fully grown when Sweetie was 5.

5) If Spike is a dog then he de-aged like 10 years, otherwise he would be an old arthritic dog in EqG if he kept his age as the same one as the CMC.

6) And of course Celestia and Luna are like 1834 years younger in Humania than they are in Equestria.

In conclusion, Humania ages are basically totally unrelated to the show and can be safetly ignored, they are just one of those things that don't match with Equestria, like, say, DNA.

If Sunset got de-aged 10 years that's still less than Celestia or Luna (and about the same as Spike, probably), and hardly a stretch.

So our best bet is to simply keep to what evidence we do have on the Equestria side, which is:

From the movie:

Sunset was Celestia's student before Twilight. Celestia says "not long before", but now how long, then again, Celestia is over 1000 years old, time is on a whole different scale for her, could mean decades, could just mean that she was the one immediately before Twilight.

From the comics what we can get is from this page:

1) Sunset was Celestia's student after Twilight was born.
2) Sunset left Equestria a full grown mare when Twilight was still a blank flank filly that was still being foal sat.
3) Sunset not only left Celestia's tutelage, she also dropped out of the School shortly after a mid term exam.
4) By the time Twilight got into the school the roof of the building had been fixed, so Twilight didn't immediately become Celestia's student after Sunset left.
5) Even Cadance was still not fully grown when Sunset left:


(Of course, Cadance is an alicorn, so she might age differently, but she appears to be roughly the same age as Shining Armor)

There's no direct was to compare Shining's age, but he still was not fully grown either when Twilight was still a blank flank, unlike Sunset:


(Notice he's grown about the same as Twilight has since she was a blank flank)

Back to the show, Cadance and Shining appear to be late 20's early 30's at the least, just for reference a captain in the US army is usually around 27 years old, so he would have been at least around that age when they got married.
Average age for army ranks for officers, so a college education is expected and the starting age being around 23 years

Of course Equestria seems to work on a different system and Shining seems to be a higher rank, but lets say 28 + 1 year after he got married and Twilight became a princess before the events of EqG.

So, in the time Sunset was gone (while she was already a full grown mare):
1) Cadance went from foal sitting teenager to fully grown alicorn, to regnant of her own empire.
2) Shining went from teenager, to college student assuming it's required for an officer, to a rising to the rank of captain, to getting married about a year before Twilight became a Princess.

So really there's no sense in trying to deny it, Sunset is at least as old as Cadance or Shining, probably actually older since they were still both teenagers when she left and she was already fully grown and apparently studying the equivalent of a college education (the School seems to cover a very large number of grades).

So a figure of 10-12 years is very much appropriate if we assume Cadance and Shining were around 15-17 when Sunset left.

Now, why did she do for all that time? Well, i don't know why assuming she was in highschool for the entire duration is a thing, she could have gone to Humania, gotten a job, familiarized herself with the world, come back to Equestria when the portal opened to check on news (she did know Twilight existed when she came back, which she couldn't have if she never came back after her original departure, since Twilight wasn't Celestia's student yet).

She might have only joined Canterlot High in preparation for her final return to Equestria, and maybe the human sunset is already out of the picture for being much older (or, my personal take, human Sunset also ran away from her own home and has been missing for 10 years).

As for her not being any older, my take is that Equestrian magic grants either immortality or very slow aging to Equestrians in Humania, and it's the reason why the Sirens are still around after 1000 years and still look like teens themselves, despite being all but cut off from Equestria and surviving on scraps.

4958726

This is no evidence, being Celestia's student does not exclude her being also a student at the School,

See Dream_Seeker's post above yours. It is stronger evidence against (2a).

Not if we go by the comics,

We don't.
For example, using the comics page you posted, we see:
(1) Moondancer being completely unlike what was (later) depicted in show canon. And, much older than Twilight.
(2) Lyra, Minuette... and the entire troupe being much older than Twilight. Even though they were the same age as (later) depicted in show canon.

So the comics is only useful for knowing Sunset's history in broad strokes, because we have no other source. It breaks down upon close examination. We would have to discard most of your reasoning that is rooted in comics minutiae.

Bear in mind, I like the idea of Sunset being much older than Twilight. However, if you are after canonicity, then your post becomes invalid where-ever it's based on the comics as evidence.

In conclusion, Humania ages are basically totally unrelated to the show and can be safetly ignored, they are just one of those things that don't match with Equestria, like, say, DNA.

None of which is relevant to the quote you were replying to, so I'm not sure what the point was.
If you just wanted to say something that came to your mind, you don't have to frame it as a reply to a quote.

Sunset was Celestia's student before Twilight. Celestia says "not long before", but now how long, then again, Celestia is over 1000 years old, time is on a whole different scale for her, could mean decades, could just mean that she was the one immediately before Twilight.

When Celestia said "not long before", she really meant "not long before" by human/mortal standards. There was already a long discussion regarding this tidbit; the most sensible approach is that Celestia meant exactly what she said.

As for her not being any older, my take is that Equestrian magic grants either immortality or very slow aging to Equestrians in Humania, and it's the reason why the Sirens are still around after 1000 years and still look like teens themselves, despite being all but cut off from Equestria and surviving on scraps.

That makes sense for the Sirens because they're immortal in the first place. It doesn't apply to Sunset.

4959057 thanks for pointing to my posts, that is the exact reason why I put that summary in the first place

4958726 trying not to sound rude (have a knack for doing that by accident), but if you take the time to read the whole discussion, the general (or at least, mostly accepted) opinion about the comics is that, most of the time, they take a different approach and/or order than the main show, and, therefore, are not a very reliable source for evidence in cases like this...

examples: Moondancer appearing in the comics previous to Amending Fences, as a fashionable unicorn with Fluttershy-length mane; and the Sirens being sent straight to modern time Humania (I'm liking that name for the human world) by the mirror portal

I don't know how many people will agree with what I wrote, but I did try my best to summarize the whole discussion in this post, in case you haven't read it yet: 4947274

Again, if I sounded rude in any form, apologies, no hard feelings, OK ?

1840748
so, can I ask a probably obvious question? I just started a new Sweetie Bot group, but I have no idea how to add a story or folder! help please?

Well, I'm really late to the party, but I figured it wouldn't hurt to toss in my two cents.

I'd like to start off with Celestia's comment about Sunset being her student not long before Twilight, I think it actually is fair to say that it means something different than what we think of as a short time. Don't get me wrong, I completely agree that it does stand to reason that what she's saying should make sense as the ponies understand it. However, we have to take into consideration the possibility that the ponies have considerably different lifespans than we do. Several pieces of information we get in the series imply that even your average ponies - not just beings like Discord or the Alicorn Sisters - live a fair bit longer than your average human.

We know that Granny Smith was alive when Ponyville was founded. According to Twilight's statements about Ponyville's traditions in Winter Wrap Up, Ponyville must have been founded at least two centuries prior to the WWU that we see. Given that Granny Smith wasn't an infant when it was founded, that would mean that Granny Smith is over 200 years old. And that's assuming that Twilight's statement refers to the bare minimum necessary for "centuries" to be applicable. So even if we work under the assumption that Granny is at the upper limit of a pony's lifespan (much like people living to 110+ in our terms), and that earth ponies live a bit longer than most, we're still talking about an average pony's life expectancy that's well over our 70-80 years, likely going into 100+.

Furthermore, later in the series we see something interesting in Pinkie Pride: 21 candles are shown on Rainbow Dash's cake. Not that unusual in of itself, but then consider that this appears to be a round cake, and we only see one side of that cake. Meaning that unless Pinkie and Cheese inexplicably decided to only put candles on about half of the cake, there should be about the same number of candles (obviously not counting the individual candle at the top) on the part of the cake that we don't see, if not a few more. That cake implies that, rather than being 21, Rainbow is probably closer to being somewhere in her 40s. I might be tempted to play that off as an animation error, if not for the previous information about Granny Smith that implies she's several years past 200. Because if being 200 years old is equivalent to being around 100+ in human terms, then 40 would be something along the lines of 20 in human terms. That's surprisingly consistent, especially for episodes that take place so far apart.

So basically, on several occasions the show gives us information that implies your average pony can live for over a century on average. It's not Celestia's age (and the perspective that comes with it) that implies "a short time" is different than what we think of, but rather that it's very possible the average pony would have a different idea of "a short time" than us. If an average FiM pony can live to somewhere between 100 and 200 years (if Granny is over 200, and Dash isn't really considered old despite the implication that she's in her 40s), then a five to ten year gap really could be classified as a relatively short time for everyone involved.

This also does quite a bit to help cover some of the apparent inconsistencies in their ages that we see in the comics. Once ponies reach their version of late teens/adulthood, it becomes pretty hard to tell them apart unless there's a particularly big age gap. If ponies really do have lives that long, it's entirely plausible that their education system keeps them in school for longer than ours would. Taking the proposed life expectancy (and the possibility of longer schooling that could come with it) into consideration, it's very possible that the foal Twilight we see in the comics became Celestia's apprentice after Sunset left, and then grew into a more adult appearance before they had all finished their education. Especially with Twilight being a genius obsessed with learning, who could very well skip a few grades to end up with her pre-Ponyville friends despite the age gap.

This also helps explain a bit about Cadance and Shining Armor's high positions. If they were mid/late teens when Twilight was a foal, then it would be a bit odd for both of them to get such high positions (Shining in particular, as it's a law enforcement/military style position) despite likely only being in their 30s during the series. On the other hand, with more years under their belts (and more training/education along with those years), they would have much more time to prove their worth while still remaining relatively youthful by pony standards.

As for the human side of things, if that really is how ponies in Equestria age then it also implies a thing or two about how they're converted into human form. We clearly see in the various Fall Formal pictures that Sunset didn't show up in the human world as we see her in the films. She was visibly younger, with a body type closer to the CMC and the Humane 6 in their photo from a few years earlier, and grows into the older Sunset that we see in the films. Since Twilight also appears in a body clearly in the same age range as her friends' counterparts and Sunset, this means that it most definitely doesn't alter their ages by a fixed amount. That is to say, it obviously doesn't just spit you out in the high school freshman age range. It's definitely adjusted based on some other factor.

As others have pointed out in the topic, there's also a fair amount of evidence showing that time doesn't pass differently between the realms, and the Sirens really don't serve as very good evidence to the contrary. We have to remember that the Sirens didn't pass through the mirror. Starswirl banished them through an unknown method, but the visuals we see during the story suggest he used a spell. If he didn't use the mirror, we can't say for certain that all of the conditions applied when using the mirror would be applied to them. It also means that we don't know what time period they arrived in when they were sent to the human world. They give no indication of how long they've been in the human world, so they could have arrived a thousand years before we first see them, or they could have arrived days before we first see them. Personally, I always felt their dialogue at the beginning suggested they'd been around for a while, but it's still hardly solid evidence.

It's also pretty safe to say that EG1 and EG2 took place a minimum of several weeks apart, and probably longer. First of all, the school has already been fully repaired by the time that the Dazzlings arrive. Sunset blew away the entire front entrance to the school - doors, walls, roof, and all - and made a large crater right out front when she was defeated. That's not exactly a one day construction job. Then Celestia says that the musical showcase will likely be the "one of the most exciting events at CHS since the Fall Formal," indicating that there have in fact been other school events since then. Meaning that not only have they had time to make repairs (and really, there's no way that classes were being held with the school in that condition), but they've had time to have other events since the repairs were made. We also know that Rainbow Dash didn't start organizing the Rainbooms until the musical showcase was announced, yet they've apparently been preparing for it long enough to be determine that their magical traits start appearing when they play and to become familiar enough with it that they aren't surprised at all. Fluttershy and Dash have also had enough time to write several songs, and the band has had enough time to rehearse Dash's songs enough that they can play some of them without any problems aside from outside interference before the showcase begins (as shown with "Better Than Ever").

So yeah, it's pretty safe to say that it doesn't universally reduce everyone to a certain age, and that time doesn't pass differently between the worlds (or at least not to a particularly noticeable or relevant degree). Of the theories I'm familiar with (excluding those two, of course), the one that I've always felt worked best was that the mirror simply matches the Equestrian person to their human counterpart. So if Sci-Twi was five, Princess Twilight would come out of the portal with a five year old human's body. If Sci-Twi was seventeen, Princess Twilight would come out of the portal with a seventeen year old human's body. If Sci-Twi is twenty-three, Princess Twilight will come out of the portal with a twenty-three year old human body. Of course, that also brings up the question of what would happen if the human counterpart was dead or hadn't been born yet, but I've yet to actually see any explanation for how they're aged that doesn't bring up any problems.

Well...that's my unnecessarily long and rambling take on things.