A soft tapping sound echoed through the hallway. "Luna? May I come in?"
No response came from behind the door. It was already open a crack, so Princess Celestia waited a few seconds before entering anyway. Her little sister lay sprawled out on the guest bed, face down.
"It's going to be okay, sister," Celestia offered in a slow, soothing tone. As she stood beside the door, her mane and tail gently rippled through the air behind her, their magical aura heralding all the vibrant colors of Dawn's aurora.
Princess Luna turned herself face-up and sighed. She wasn't wearing her shoes or crown, and her dull azure curls were a tangled mess. "I know that, Celie," she grumbled, slowly pulling herself upright.
"I'm afraid this guest suite will have to do until the masons finish renovating the castle. It will take some time to construct a room befitting of a princess." Celestia shut the door behind her.
"These quarters more than befit me, and I do not care about such things," said Luna, holding her lips in a sour pout. "I have but one desire unfulfilled. My stars are departed, sister. My tail and mane are now plain and unremarkable; my stature, insignificant."
Celestia nodded slowly. "Yes. It surprised me too," she said.
"Why should it, though? It is fitting, is it not?" asked Luna, arching her eyebrows. "I have earned this frail body with my treachery. Gaze upon the product of mine own degeneracy, and behold the foal laid bare!"
"Nopony thinks you are a foal, Luna." Celestia walked over to her sister and sat beside the bed. Even with the bed propping Luna up several hooves, Celestia met her tiny sibling eye to eye.
"To be certain, I do not mean foal-ish. I mean an actual yearling, Celie." Luna blew a puff of air upwards at her forelock. The disheveled curls bobbed briefly.
"I meant it in both senses." Celestia levitated a brush from the nightstand over to Luna's head and began untangling the knots. A look of irritation flashed across Luna's face, but it faded.
"In full candor, this may be for the better. The beast I became too closely resembled my former appearance. The ponies I confronted in that village would likely flee from my terrible royal countenance, had I yet retained the stature of an elder alicorn," she said, pulling her head back against the strokes each time the brush met resistance. "Fie! I forgot how tiresome such a mane can be. It has been nearly a century since I last had to endure this."
"Imagine how I feel. It's been more than a millennium since I had the privilege of combing my sister's hair," said Celestia, wearing a wistful smile. Her own glowing mane flowed mesmerically behind her, despite the absence of a breeze. It was impossible to make out individual strands.
Luna snorted. "So much time has been lost to me. Now to call you my older sister is a tremendous understatement—no offense is intended, of course. I trust you had an easy run of matters without my troublesome presence, lo these many years."
Celestia paused her brushing and clenched her jaw. Her eyes were misty. "Being without you was... excruciating." There was a long moment of silence, then the brushing resumed.
"I am sorry, dear sister," whispered Luna. "I did not intend—"
The elder sister tapped Luna on the muzzle with her telekinesis. "It's fine, Lulu. The nightmare is finally over, and you are with me again. All is well now."
Luna shook her head. "Neigh! I have not lived this thousand years as you have. I was not conscious for the period of my absence, and did not suffer as I have made my innocent sister suffer. I am deserving of punishments most foul and tragic."
"No, you are not. There will be no further punishment." Celestia finished brushing Luna's mane and began attending to her tail.
"Fine, then! Should a suitable torture not be provided to me daily, I shall enact a means to punish myself," said Luna.
Eyes wide, Celestia dropped the brush. "Luna! Don't speak like this," she said. "You made but one mistake! You've atoned. I want to see you happy. I want to be with my sister again."
Luna's eyes cast downwards. "Yea, yea," she mumbled, and sighed. "I know I should be pleased at this turn of events. I do not mean to be so grim."
"You'll feel better soon." The brushing of her tail resumed. "Things will return to normal, with you ruling by my side. You'll see."
"My Stars. I do not deserve a sister as remarkable as you, Celie." Luna looked back up, and there were tears in her eyes. "You wish for me to rule, after all that has transpired?"
"They're building a second throne as we speak." Celestia smiled wide.
Luna laughed. "I cannot yet grip the Moon. I have made many an attempt," she admitted.
"I can manage it until you get the hang of it again, which I'm certain you will in time." The brush continued to comb its way through Luna's stubby tail, patiently straightening and smoothing through all the confused and tangled fibers.
For a moment, Luna turned her head and looked out the window at the pregnant Moon. "Ah! My dearest sibling, ever attentive to the finest detail. You chose this room so I could see it rise," she realized.
"Of course." Celestia finished the process and replaced the brush on the dresser, now thick with blue hairs. Luna felt a tight knot within her barrel unravel.
Flipping her silky tail upwards, Luna looked back and forth between its dull blue hue and the shining, starry sky beyond the window. "Perhaps, do you suppose, I might earn it back someday?" she whispered.
"My silly pony. I have no doubt that you will," said Celestia, petting Luna's now much smoother mane.
As Princess Celestia embraced her little sister in a close hug, Luna finally smiled, and her legs gripped her sister back more tightly than the Stars themselves cling to the Heavens.
And there, in the middle of their embrace, the tiniest twinkle appeared in the tip of Luna's tail.