Celestia lit her horn and lowered her head, setting the sun below the horizon. The sky was streaked with orange, fading to purple, before Luna took hold of the moon and brought it up to begin the night. Celestia turned her eyes upward as stars slowly appeared in great swirling swathes above her. It was slightly sad, she reflected, not for the first time. No matter whether enough had been accomplished, the day was over. She knew that ponies needed to rest though, and at least they could do so under her sister’s watchful eye ...
Beside her, Luna yawned widely, squeaking at the end. Perhaps not so watchful tonight. Celestia smirked and raised a wing to lay over Luna’s back. “Is little Luna tired? I know it’s been a long day …” she asked, partly worried, partly teasing to hide her worry.
Luna shrugged her wing off, annoyed. “Stop it. I am a big pony now, I need not your tiresome ministrations.” A bell chimed mournfully in the distance, eight times. Luna sagged slightly. “I … I do not mind standing vigilant for such times, when I must. You have done the same for me, for far longer …”
That was not the way to make Celestia less worried. She watched Luna’s downcast expression. “That doesn’t mean you need to repay me, sister.”
Luna stood up straighter, looking out over Canterlot. It was clear that she would do her duty, regardless. “I know.”
Celestia watched her for a moment more, before turning her gaze out to the city as well. Luna always tried so hard. It would only be right to let her do as she wished.
They didn’t have much time, as always. Raven, her dependable scribe, had deposited a mountain of papers on Celestia’s desk that needed to be shrunk before she went to bed. That was what happened when she lost her mind and went on an adventure for a day. At least she had Kibitz to take care of everything else.
Still, she was glad it had happened. Star Swirl was one more mystery laid to rest, although …
She spoke up again, her brow creasing. “Luna, you never told me what was wrong.”
Luna turned towards her, a questioning look on her face. “What do you mean?”
Celestia explained, “When I didn’t remember the last thousand years, I asked you why you used to be so quiet. You never answered me.”
Her sister thought back, remembering what she had said. “… didn’t I? I was hoping you would get your memory back before I had to tell you, but …”
She shook her head. “No, before that. You were so withdrawn, even all the way back then. We hadn’t even found the Elements of Harmony yet. What made you like that?”
Luna understood and mentally cringed. Oh, that. “Oh. Uh … it’s nothing.”
Predictably, Celestia frowned. If there was half a reason to worry, that was a whole reason too much. “It’s not nothing, it’s important. You can talk to me about these things, I don’t want you to be upset if I can help it!”
She bit her lip. How could she make her sister stop? There was no way Luna wanted to tell her, it was too embarrassing. The only thing Luna could think of was the truth – with bits cut out. “I know that, Celie, but I have taken care of it. It is nothing of concern.”
Celestia blinked. The little Luna that needed her help had turned into a confident and independent younger princess, capable of solving her own problems. When had that happened? “… if you’re certain. I am always here for you, sister.”
There. She was safe, as long as Celestia got distracted by something else before she started worrying again. “And I am here for you. Goodnight, sister.”
“Goodnight, Luna.” With one last smile, Celestia turned and walked back inside to make decisions for the fate of Equestria.
Luna watched her go. That had been too close. It probably wouldn’t have been too bad, to let her know, but she didn’t need to find out. No, what she needed was a sister she could rely on. Luna spread her wings and took off, to go protect Equestria from the terrors in the night.