"Who's that?"
The thing that most ponies forget, when it comes to colts and fillies, is that they have a tendency to notice things. Like adults on just about any world, they think that a child is incapable of noticing something that that is not brought to their attention, and that they cannot see details. Anyone who has spent any amount of time with the young will tell you that this is not the case, and that the young are actually almost disconcertingly aware of their surroundings.
Galaxy was the principal of a school, one that catered almost exclusively to small colts and fillies, so she really should have expected young Morning Glory to see the photo on the older unicorn's desk. Had she thought about it, she'd have tucked it away and hid it when she came into the room, but now it was too late.
For Glory was examining, with great interest... the photo. It was a photo of an easily recognizable filly, given that the older version was right here in the room. She was standing there, grinning, with another young filly hugging her. The other young filly had a bright pink coat, and a long, blond mane and tail, with a bouquet of roses as her cutie mark. She was also, quite clearly, an earth pony. And there was, to anypony who had eyes, a strong family resemblance between the two.
"That is," Galaxy said, after a moment's pause, "myself and my sister, Floral Bouquet, when we were your age."
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There is an event called an epiphany, a moment of startling, stunning realization that can change how one sees the entire world. In that moment, Morning Glory had such a moment.
'That's why she's been acting so weird,' Glory thought to herself, as she looked at the photo, her own face reflected in the glass of the picture frame. She saw her own face, and then the face of the young filly in front of her, and could clearly see the resemblance. In fact, were it not for the different color schemes, the two could practically be twins. Seeing it in front of her, with her own eyes, there was only one conclusion she could make...
Morning Glory was Galaxy's... niece. She was very obviously Floral Bouquet's daughter.
"Where is she now?" Glory asked, trying very hard to steel herself for the answer she expected.
"I didn't always live the peaceful life I do now," Galaxy said, as she used a spell to pick up the photograph. "Like Twilight Sparkle, and many before her, I had my share of adventures, and friends who shared them with me... and sad to say, I made my fair share of enemies during those escapades. My sister was with me for all of them... up to the end."
Oh. Glory asked, quietly, "What happened?"
"I'm sorry to say that I can't tell you," Galaxy stated, seeming to form her words very carefully. "Not every adventure I went on with my friends were ones that could be discussed openly. For some of them, my friends and I were sworn to secrecy for at least the next ten years. When you're older, though, I could tell you... if you wish."
Glory turned, and then nodded. "I'd like that."
So many things suddenly made sense to Glory: Why she'd been kept in Cloudsdale, even though she might have had relatives still among the living? Because whatever craziness had gone on in Galaxy's life had come with terrible consequences, and by her own admission, left her with enemies. Enemies who might come back, looking for revenge... and might be willing to use a filly to get it. So what better, safer place to hide a filly than in Cloudsdale, a city accessible only to pegasai and those with the spells that allow them to cloud walk. Cloudsdale, a city that held both the main bases of the Equestrian air force and the Wonderbolts, not to mention more on and off-duty guards, per capita, than even Canterlot itself. The only way she'd be safer... is if she was under the wing of one of the princesses. That was why Galaxy was acting so weird: She wanted to tell her niece everything, but doing that would mean that Princess Luna wouldn't be able to foster Glory, since she already had family. So... to keep Glory safe, she had to keep quiet, even if it hurt her inside.
It all made so much sense...
Glory took a deep breath, and then said, "Okay, so this is your study. Can I see the rest of your house?"
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"Hey mommy!"
As the tour of Galaxy's well-kept home concluded, Golden Glow walked up, holding a newspaper. "Look! Look!"
Galaxy studied the newspaper, as well as the photograph on the front page. Glory snuck a peek as well. The words and picture were... surprising, to say the least...
"Excelsior, The Final Superhero Of The Golden Age, Announces His Intention To Retire At The End Of The Year," Glory read aloud. The stallion in the picture wore what could only be a superhero's costume, complete with a cape and mask. Since it was a black and white photo, it wasn't possible to say what the color scheme might be. Confused, she asked, "Superhero? Like in the comic books?"
Goldie giggled, and said, "No, you've got it exactly backwards: The heroes in the comic books are just like the ones in Manehattan."
Fair enough. "Okay," Glory admitted, after a moment, "I can't argue with that. But what did they mean about 'The Golden Age'?"
Galaxy explained, in a tone that reminded Glory of her teacher back in Cloudsdale giving a lesson, "Nearly one hundred years ago, there was a comet that was about to collide with Equestria, on a direct course for Manehatten. Fortunately, Princess Celestia was visiting the city at the time, and was able to use a spell to destroy the comet. However, like the Secretariat Comet, which causes spectacular increases in the latent powers of magical creatures when it nears Equestria, this comet also possessed powerful magical energies. The destruction of the comet showered the city with waves of magic, as well as fragments of itself. Since then, individuals possessing abilities well above and beyond that of the average pony, colloquially known as 'Superheroes' and 'Supervillains', have regularly appeared. The term 'Golden Age' refers to the first generation of those 'heroes' and 'villains'."
"So... why aren't they out and about, doing stuff?" Like say, fighting Lord Tirek, or Discord?
Galaxy smiled, and gave a brief nod to Glory, saying, "An excellent question, and the answer is simple: 'Superheroes' and 'villains' only have powers while in the presence of the magical energy of that comet, much like the energy generated by the Secretariat Comet. Since the city is still, even now, soaked with the energy of that comet, those with powers are able to use them within the city limits. However, outside of the city, those powers vanish very quickly. Which is fortunate: As I mentioned, there are villains inside of the city, as well as heroes, so they are just as bound within the city limits as the heroes are."
Looking over at Goldie, Glory asked, "And why are you so excited about Excelsior retiring?"
Goldie stuck out her tongue, and said, "I'm not excited about him retiring. I'm a huge fan of his, and normally, I'd be sad, but I'm excited because he's going to be making a major public appearance next week, and he'll be signing autographs!"
Glory put two and two together, and asked, "And you're expecting to be in Manehattan next week?"
Galaxy nodded and said, "Indeed. I have a conference to attend in Manehatten in a week's time. And we should be able to visit the event while we're there."
Glory looked at the paper again, and asked, still a little puzzled, "But if the first generation is called 'The Golden Age', what is the current generation called?"
"The Silver Age," Goldie and Galaxy answered, simultaneously. They didn't try and jinx one another, though.
"Why's that?" Glory asked, surprised. It sounded almost like an insult.
Galaxy gave a small chuckle and admitted, "It is kind of a funny story..."