There's something most parents try to teach their children when they're still very young: never pick at a scab. It just keeps it from healing and may even reopen an old wound. Right now, Trixie was picking at a scab, and Twilight feared what it might reopen in Starlight.
Starlight looked at her friend silently, then shook her head.
"No, Trixie. I can't teach you that spell."
"But why not?" Trixie whined. "It's a great spell! Trixie wants to learn that spell!"
Starlight shook her head again.
"That spell was a mistake. I never should have written it. I definitely never should have cast it."
"You're just being dramatic," Trixie sniffed. She speared another piece of pancake with her fork and then gesticulated with it at Starlight. "And Trixie knows all about being dramatic."
"I'm not being dramatic," Starlight snapped back, growing visibly irritated. "That whole thing was a terrible idea, and I figured it out about ten seconds after I cast it on Sunburst and me!"
Twilight had only heard about it after the fact, but could easily imagine the fiasco. Sunburst was Starlight's only friend from childhood, and she’d been overjoyed when he'd paid her a visit in Ponyville. The problem was that the two, who had been so close as children, had been separated so long that they found they had little in common anymore. Starlight hadn't taken it very well, and so she'd hatched a plan to rekindle their childhood friendship.
"I think turning the two of you into little foals to play your favorite board game again was sweet," Trixie replied.
"Well, unfortunately, Sunburst didn't think so!" Starlight shot back. She sighed. "Trixie, I thought you knew me better than this. Please stop, okay? Besides, the spell's too complicated for you to learn. Not now, anyway."
Trixie scoffed as she swallowed another bite of her meal.
“Were you both not praising Trixie as ‘gifted’ just a few moments ago?” she sniffed. “Besides, I’ve cast age spells before.”
“Well, my spell isn’t an age spell, for one thing,” Starlight replied, poking at the remains of her own meal on her plate.
“And you were using the Alicorn Amulet to boost your powers when you did,” added Twilight as she took a bite of her own food. “Darn it,” she thought. “It got cold again.”
Trixie looked confused.
“Wait,” she said. “Why wouldn’t you use an age spell to turn yourself into a child?”
“Because I still wanted to turn back into an adult when we were done,” Starlight replied. “Age spells are complicated. They can also be really dangerous when you don’t know what you’re doing. And you never, ever want to cast one on yourself that would make you too young.”
“Why not?” Trixie asked, looking genuinely interested. “Don’t you just stay an adult inside and get a little body again?”
Starlight sighed at her friend’s naiveté. She had a boundless confidence that was often born of utter ignorance, and teaching her real magecraft required a lot of hoofholding.
“No, it doesn’t work like that at all,” said Twilight as she took another bite of her moldering meal. “The thing about age spells is that they can really mess up your memory if you’re not careful. It’s all about going too far back with your brain development.”
Trixie smiled and nodded, as she brought another forkful of food to her mouth.
“You have no idea what I’m talking about, do you?” said Twilight with a note of exasperation.
Trixie smiled and shook her head as she chewed her food. Starlight sighed.
“Okay, think of it this way,” she began. “Imagine your brain is a house. It starts off small, with a couple of rooms. Your memories and experiences are like books and pictures you store in it. Follow me so far?”
Trixie smiled and nodded. Starlight and Twilight exchanged a worried glance.
“Oh, stop that, you two!” Trixie exclaimed. “I’m not a total idiot. I get it! Go on!”
“Okay,” Starlight continued. “As you mature, you add on more rooms to the house. It gets bigger, and you fill it with more stuff. You build up more experiences and more memories. Anyway, by the time you’re all physically grown, your house is pretty much as big as it’s going to get.”
“But, you can learn new things when you’re grown,” Trixie protested.
“Yes, but your brain isn’t going to get more space inside. You’re just...filling up the unused space. It’s like your house has spare rooms for you to use. Still with me?”
“I guess,” Trixie replied. “But what does this have to do with age spells?”
“An age spell can return your brain to a younger state,” said Starlight. “The trick is that you have to be careful not to suddenly make your house small again.”
A look of confusion crept onto Trixie’s face.
“Okay, if you make a child older with the spell, they’re going from a smaller house to a larger one. Understand?”
“Yes, I think so,” said Trixie.
“And if you make an adult into an younger adult, the house stays about the same size. Still with me?” asked Starlight.
“Yes,” replied Trixie, nodding smugly.
“Okay, now what do you suppose happens if you make an adult into a child? If the big house is suddenly made into a little one?”
Trixie considered it for a moment.
“It...can’t hold all the books and pictures anymore?” she asked hesitantly.
“Exactly!” Starlight replied. “A child’s brain isn’t developed in the same way as an adult brain. It can’t handle all those memories and experiences the same way.”
“So, what happens then?” Trixie asked.
“Bad things,” said Twilight, cutting in. “It can really mess someone up. Like you almost did with those two colts you turned into babies.”
Trixie looked confused.
“I didn’t mess anyone up!” she exclaimed. “I see those two little idiots all the time. They’re fine!”
“Trixie, you weren’t here when we had to clean up after our magic duel,” Twilight explained. “Fortunately, they were only babies for less than an hour, and you’d only made a couple of little kids a few years younger. But it took weeks before they were back to normal.” Twilight paused. “Or, at least as normal as Snips and Snails can be.”
“When you turn an adult into a child, it doesn’t just erase memories and leave you like you were originally as a little kid,” Starlight continued. “The spell’s designed to keep as much of your mind intact as possible. When the brain can’t handle it all, memories just start getting scrambled. Combined. Rebuilt.”
“So…” Trixie thought for a moment. “If you turn yourself into an actual child, it’d be like sticking a spoon into your brains and mixing it up?”
“That works,” said Twilight. “It’s kind of gross, but you get it. You’d end up with some memories being kept, some being erased, and others just getting combined. You might be a whole different pony in the end.”
“Not to mention that your magic would most likely be too weak at that point to cast the spell again,” Starlight added. “You’d be left a really confused little kid.”
“So, then what did your spell do?” asked Trixie.
“My spell combined transfiguration and illusion,” Starlight replied. “I wanted us to pretend to be foals, not actually become them. So, it gives you a body that looks like one without any of that messy stuff happening to your mind.”
“Well, then there’s no problem!” Trixie declared happily. “Trixie is quite adept at transformation now!”
“If you need something turned into a teacup, at least,” Spike grumbled, finishing the new batch of pancakes.
Twilight felt like hitting her head against the table. Why could this mare not take a hint and let it go? She saw a scowl creep back onto Starlight’s face. “Stop picking at this,” Twilight thought. “Why can’t you see how this is upsetting her?”
“Trixie, why do you even want to know this spell? What possible use can it be to you?” Starlight asked, her irritation now evident.
“It would be a fantastic finale for my show!” Trixie exclaimed. “Just imagine it, after my usual illusions, and perhaps a disappearing act with my teleportation, I close by transforming myself into the tiny and adorable Trixie! The crowd will cheer! Hearts will melt! And wallets will open!” Her eyes shone as she imagined the acclaim. “And I will have you know, I was a very, very adorable child. They won’t stand a chance.”
Starlight closed her eyes and took a deep breath, massaging her temples with her hooves. This whole conversation was giving her a terrible headache.
“Trixie, you can’t do this yet,” she said slowly. “I’d have to do it for you.”
“Well, maybe you can cast it on us?” Trixie asked, hesitantly.
Starlight stopped massaging her aching head and opened her eyes. She slowly turned toward Trixie.
“I’m sorry. Did you say us?” she asked.
“Yes.”
“You want me to turn the two of us into foals?”
“Yes.”
As Spike brought a platter of fresh pancakes to the table, Starlight placed her forelegs onto the tabletop and leaned forward.
“Why?” she asked.
“Because…” Trixie dragged the word out, as though embarrassed by the reason. “There’s something I think we should do together, and we’d need to be foals to do it?” She paused a moment. “Tomorrow?”
“Why tomorrow?” Starlight asked, slowly.
“Wait a minute,” said Twilight, getting up from her seat. She trotted over to a calendar tacked to the kitchen wall. It was one of several, each marked with different appointments for Twilight’s schedule. The one she was studying showed holidays and town events. “This wouldn’t have anything to do with Foal Field Day tomorrow, would it?”
“Yes!” said Trixie quickly. “That’s it exactly! I want us to go to that.”
Foal Field Day had been the mayor’s idea as a family event for Ponyville. It was meant as a lead up to Mother’s Day that coming Sunday.
“As foals?” said Starlight.
“Why in the wide land of Equestria would you want to do that?” Twilight asked as she returned to the table. “What does that have to do with learning the spell for your act?”
Trixie opened her mouth, then closed it, looking first at Twilight, then at Starlight, then at the remains of her breakfast on her plate. Finally, emitting a strangled grunt of frustration, she looked back up at them.
“All right! All right! You have me! It has nothing to do with it!” she confessed. She sighed. “I’ve just been thinking about that spell all this time, and I want to try it.” She looked plaintively at Starlight. “I’d like to just have fun as a little kid again, and I want to do it with you.”
She reached a hoof across the table and touched it to her friend’s.
“Please? I think it would do us both good.”
Silence fell across the table. The air seemed charged with tension, and Twilight felt like she could barely breathe.
“No,” said Starlight.
“Why not?!” Trixie pleaded.
“Just no!”
It was now Trixie who was growing angry.
“You were going to do it with Sunburst!” she cried.
“That was different!”
“It’ll be fun!”
“No, it won’t!”
Trixie’s eyes flashed with anger as she took a deep breath and played her final card.
“If you are really my friend, you’ll do this for me.”
Twilight’s eyes widened in horror.
“Trixie, that’s enough! That is way, way more than enough!” Twilight shouted. “What is wrong with you today?!” She turned to Starlight. “Starlight, are you…”
Twilight’s voice trailed off as she turned to her former student. Starlight was shaking, but not in rage. There were tears in her eyes.
“Don’t you understand?” she whispered.
She stood up, then pounded the table with her forelegs.
“I can’t go through that again!”
Her hooves clipped the edge of the platter of cakes Spike had just set down moments ago, sending them flying. Twilight barely had time to cast a protective bubble around herself. Pancakes slapped against it and then slid to the floor. No one spoke as Starlight panted, a mixture of anger, frustration, and... fear.
“I’m sorry,” she finally said. “I… I…” She took a breath. “Excuse me!”
Starlight dashed from the kitchen.
Neither Twilight nor Trixie said a word, both staring at the door through which Starlight had just vanished. Finally, Trixie spoke.
“I think that’s your cue to go after her,” she said.
Twilight glared at her.
“Maybe you should go after her, seeing how you just made your best friend cry!”
“No,” replied Trixie, quietly. “I really think you should go.”
Her eyes flashing in anger, Twilight rose, levitating one of still warm pancakes scattered over the table. She rolled it into a tube and, taking a bite, headed for the door.
“What are you doing?” Spike asked.
“It’s clearly the only way I’m getting something hot to eat this morning,” Twilight shot back. “Thanks, Trixie. You really know how to make a mark on an occasion!”
And with that, Twilight ran from the room.
Twilight galloped through the hallway and up the grand staircase to the second floor, where their bedrooms lay. She knew exactly where Starlight would retreat to. She angrily gulped down the last of the pancake as she arrived at Starlight’s bedroom door. She tested the latch. It was locked. She took a deep breath and tried to calm herself.
“Starlight?” she called softly, knocking on the door. “Can we talk, please?”
There was a pause, and then the latch glowed as Starlight magically unlocked it from inside. Twilight opened the door and stepped in.
Starlight Glimmer’s room was an eclectic mixture: a stuffed bear in wizard’s robes in the corner, books of advanced magic scattered about, potted plants, a couple of kites on the floor, a poster of a butterfly on the wall. It looked like the bedroom of the world’s brightest eight year old.
Starlight sat on the floor, leaning up against her bed. Her horn glowed as she levitated a spell scroll in front of her as she read it over. Twilight silently trotted to the bed and sat down next to her. They sat side by side, in silence.
“Well,” Twilight finally said. “That sure was a thing that happened, huh?”
Starlight said nothing.
“So, is that the…?” Twilight asked, indicating the scroll.
“Yeah, it’s the spell,” Starlight replied, passing it to Twilight. Twilight’s horn flared as she telekinetically grabbed it, then began reading it herself.
“This is really good stuff,” she said. “I like how you augment the transformation with an illusion.”
“Yeah,” said Starlight, quietly. “You never know what crazy old Starlight’s going to come up with next.”
“Don’t say that about yourself!” Twilight replied, sharply. Starlight sighed and stared at the floor.
“Twilight,” she said softly. “Sometimes I wonder if there’s something really wrong with me.”
“You just got angry, that’s all,” Twilight replied, putting a hoof on her shoulder. “And I have no idea what’s got into Trixie. She’s acting just awful today.”
“Trixie, what are you doing here?” Spike asked, watching Trixie continuing to eat. She had finished her plate and now began picking over the leftovers on Twilight’s.
“Trixie is having breakfast and visiting her friend,” she replied simply.
“No, you’re stealing Twilight’s breakfast and you just made your best friend cry.”
Trixie said nothing, and continued to eat. Spike watched for a few moments, then grabbed Twilight’s plate away. Trixie put down her fork and turned to face the diminutive dragon.
“So?” she said.
“So, what are you doing here?!” he exclaimed. “Why are you acting like this? You saw how upset Starlight was getting, but you wouldn’t stop! Why did you have to bring up that whole thing with Sunburst? Why would you ask her to turn you both into foals?! What’s so important about it that you’d make her that upset?!”
Trixie was silent for a few moments, then levitated her fork again and stabbed at Twilight’s plate. Spike moved it out of the way, glaring at her. Trixie sighed.
“Trixie was pushing.”
“What’s that supposed to mean?”
“It means,” Trixie replied, “that I was pushing Starlight about her childhood so that Twilight would finally ask her about it.”
Spike regarded her for a moment, then moved the plate back toward her. Trixie rewarded herself with a bit more of Twilight’s breakfast.
“What about her childhood?” Spike asked.
“What do you two know about it?” Trixie asked in return.
“We saw it,” Spike replied. “Like, we were literally there. Starlight took us back to when she was little and we saw when Sunburst left her to go to magic school. And the whole thing with her getting obsessed over how special talents end up driving ponies apart.”
“Ah,” said Trixie. “You mean you two saw a few crucial minutes of her childhood. Did you ever stop to wonder about the rest of it?”
Spike considered the question.
“No,” he finally answered. “And Twilight saw that she doesn’t like to talk about it, so she never…” He stopped, realizing what he was about to say. “She never pushed her on it.”
“That’s the trouble,” said Trixie. “Everyone is scared to push her, like she’s made of glass and she’ll just shatter.” Trixie chewed on the cold pancakes for a moment, ruminating. “Trixie has tried, but she can’t get through. That’s why she came up with a plan.”