Shortly thereafter

“The Princess sent me out here to get you. She wants you to speak to her personally,” said Rainbow Dash to Twilight.

Twilight noticed that Rainbow Dash’s eyes looked as though she had just been crying. Pretending not to notice, she turned and entered the throne room. Walking towards her was Princess Celestia.

“You’re blessed to have such a loyal and dependable friend,” said Celestia. “She really needs you now, Twilight.”

“I know. It just breaks my heart to see her being unable to fly. She truly was majestic.”

“I know Twilight.”

“Princess…” said Twilight before drifting off.

“Yes, Twilight,” asked Celestia, prodding her former student along.

“I was wondering if it would be possible to use your alicorn magic to give Rainbow Dash her ability to fly back.”

“What do you mean?”

“I mean I didn’t have wings, but thanks to you, I now have a pair,” said Twilight, spreading her wings out to emphasize her point.

“I understand Twilight,” said Celestia. “Unfortunately, I can’t oblige.”

“Why not?!” shrieked Twilight.

“The transformation spell only works on unicorns.”

“What? Why?”

“You see the spell gives one wings and gives one a unicorn horn.”

“And?”

“Well Twilight, as you well know, a unicorn’s horn connects to one’s brain. If I were to conduct that spell on a pegasus or Earth pony, then that would require rewiring their brain to connect to their unicorn horn. On an unborn foal, that would have a negligible impact on them long term. However, on a fully mentally developed adult like Rainbow Dash, it could result in permanent brain damage. I don’t think that we want that to happen now do we?” said Princess Celestia.

“Sorry, I didn’t kn-”

“It’s okay Twilight. I wish that I could help Rainbow Dash and all of the disabled ponies out there but even an alicorn like me has her limits.”

Celestia continued, “However, there is one thing you can do. Be there for her whenever she needs you. Help her discover the new destiny that awaits her.”