https://www.fimfiction.net/story/418440/those-forty-years (The sequel is out! Check it out here. Check out my latest blog for why it's on my co-author's profile instead of this one.)
A legendary magical discovery leads the protagonist Twilight Sparkle through a chain of events that not only explain Celestia and Luna's history, but a history about herself that even she could not have imagined.
Co-Author profile link.
WE HAVE COVER ART! 
8/3/2016 Check the source for the artist. (permission was given)
Chapters (15)
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I'll have a look then, thanks for the comment.
Now I have issues. here. While admittedly the full background of the sisters are unknown, we do know that they came to rule AFTER Discord. I don't see them or their parents in Canterlot. so interesting idea you lost me here.
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"Now I have issues. here. While admittedly the full background of the sisters are unknown, we do know that they came to rule AFTER Discord. I don't see them or their parents in Canterlot. so interesting idea you lost me here."
See that AU Tag? I know I didn't
6205472 hence why I didn't downvote. I just stopped reading.
Interesting story so far :)
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Co-author Counter: The sisters that we saw that took over after discord's reign were fully grown, thus it can be argued that before hand when they were FILLIES their parents could have been in charge. This could be a span of who knows how many years. Furthermore we don't know how long discord was in charge of the world or how old the two sisters were when they defeated discord. It is very possible they came into reign and lost their reign when discord took over. Thank you for criticism.
6205497 Thanks, Hurray!. Thanks for the comment, glad to see you enjoying it.
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There is only one more thing to say about it mooooore!!!!!!!!!
6205498 your welcome, I go under the idea that Platium's line ruled till Discord. That's me but good luck with the story.
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Soon... soon.s3-ak.buzzfeed.com/static/enhanced/terminal01/2011/4/1/17/enhanced-buzz-28895-1301694293-0.jpg
Minor quibble--unless Starswirl was never going to use the spell himself, it's likely that Twilight would have been able to. Celestia did name her as the most powerful unicorn she had ever met, so if you're talking about purely the drain on her magic she should be able to accomplish it.
Quick note, the word "fun" wasn't invented until after Luna's banishment.
In comparison, the use of "fun" as we now use it didn't come around until the 1700s. Until then, the words it derived from had negative implications.
That's either something you'd want to fix, or just an interesting bit of trivia.
6389067 It's interesting AND helpful, thanks so much for commenting and reading along while giving that interesting tidbit!
6389045 Mhm, I get what you're going for, and you do have a few interesting ideas about it.
Update on its way, and yes I'm that writer guy in the background. Sorry about how slow this has been but I've just got time to write out the chapter. Ill keep you guys updated on the progress. Most likely this will go up in a few days after the editing process. If you guys want the chapter unedited just ask.
PS: I blame college
PSS: No i wont be posting a story to my own page for a longgggg time.
PSSS: Uh.... yea.
A small Interemdum chapter is coming up along with the one after that. Double post coming soon. Also this should no longer be on hiatus as I have found some time in my schedule to write again.
Poor Twilight and Celestia, I hope everything turn out alright in the end
I hope her mother returns soon
6804450 Reread this chapter, and you'll be able to pinpoint when exactly she returns.
most say I am enjoy this story,
Smallestia and Twilight Future. BFFs 4eva!
good stoty so far :)
Hurrah! Next chapter is done and ready for editing. Expect it soon!
Awesome glad that Twilight is out! Never thought she would be planning the first Grand Galloping Galla. Can't wait for more!
lol so funny please keep updateing this story
Why is everything in italics?
Great story though.
Celestia learns to make a schedule and teaches it to Twilight so that Celestia will learn to make a schedule
I love it!
7063182 I think the italics are the inner thoughts...
Next chapter is done, it is now going through editing process.
so CUTE!
hope to read more soon
so cute need more, need more chapters,
also is surprise twilight does not meet her ancestors yet....
7095482 WELLLLLL....
You'll find out about that later.
7095482 far enough back would her family exist. In someways I'm surprised she was able to find her fiends ancestors and for teh most part they have the family name.. This isn't overly surprising for the Apples or Pies but we've not seen much to suggest how far back the Dash or Belle family goes
I wonder whose Twilight's ancestor is, can't wait to read more!
is it bad I want it adult Celestia so some how end up here to grab twilight and bring her back to her right place in time. near the end of the story
I really liked this chapter hope to read more soon
Sorry for bugging you but do you know when the next chapter will be posted?
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I'll look into it, please understand that the writing process is still in the works, but it is not the focus of myself or the co-author for our lives. Thank you for understanding.
Update: The next chapter is almost done, it'll hopefully be finished after some computer issues are dealt with on our end.
7414948 That is okay I understand thank you so much for letting me know it means a lot
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Anything for one of the readers.
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The chapter was not lost!
However it will take me about a week to get everything up and running again along with replacing the lost progress for my part. Sorry for the delay everyone.
Chapter is live.
Liking it so far.
liked the new chapter hope to read more soon
oh my i feel fight going to start, two way to rule,
Cool! I see you like great detective pikachu as well!
7553879 Of course I do! I love the concept.
sorry for bugging you but do you know when the next chapter will be posted???
Something that is buging me. They don't seem surprised at all that she is a Alicorn. And also how weak you have Twilight. She is a Element of harmony and the Princess of MAGIC. Its just kind of annoying how weak you have her.
Hope this is continued. An awesome idea and a good story. But would also like too know is Twilight going to grow into what she looks like in the picture. And finally will ther be any type of romance ? If there is kind of vote for Discord or Starswirl