When The Sun Burns Out

"Your moon is beautiful tonight, Luna."

"You tell me this every night, 'Tia. I am well aware of it by now."

A small smile split the Sun Goddess's face. "I feel like it is my duty to remind you daily that your night is gorgeous."

"Still fretting over Nightmare Moon, are you, sister?" The other mare grimaced.

Celestia hesitated before letting out a sigh, "I am. I still regret it to this very day."

"You did what you had to. I would have done the same thing, dear sister. I was blind to my actions... I let my anger take over..."

"I was just as blind as you were. I should've paid more attention to you, rather than myself... and I would hope you mean you'd also send me to the moon. Banished or not, I'd never return from the sun."

Luna let out a small giggle, a smile playing on her face. "Of course~"

The white mare couldn't help but laugh a little herself, afterward letting out a sigh.

"You really shouldn't, though. It's been nearly four hundred years since my return. I've long forgiven you by now."

"Yes, I know. I just love you enough to remind you anyways."

Luna looked up at her elder sister. She secretly hated that Celestia would be forever taller than she, but didn't mind it all that much.
She frowned slightly as she studied her sister's features. Whether Celestia wanted to admit it or not, she was getting old. The bags beneath her eyes were becoming more and more visible with every passing year. Even the colors in her mane had dulled significantly, glazed over with a pale silver sheen. It truly pained her to see her get this way, but alas, even princesses didn't live forever, and she really dreaded the day that she'd start looking the same way.

"Perhaps you should rest, 'Tia..." She offered, but the larger pony shook her head. "I have to raise the sun in a few minutes, you know that."

"You look exhausted. I can do it just fine." She pressed, a bit forcefully. She wasn't really asking. She knew for a fact that she needed a good, long rest. It seemed the older Celestia got, the more she did. "You need rest. You've overworked yourself today, and here it is early morning and you still haven't slept. You're going to kill yourself."

The princess shrugged. "I'm perfectly fine currently."

"Liar..." She muttered, glancing back up at the sky. Blue light illuminated around her horn and the moon slowly began to fall shortly afterward. "You overwork yourself and you know it. Usually, when a pony gets older--a normal pony, anyway--they don't push themselves as hard and enjoy their retirement and golden years."

"Well, Luna, I am no normal pony, now am I?" She waited patiently for the moon to completely vanish. Her horn then began glowing as well, the sun very, very slowly appearing from over the horizon. "I have a duty, and I cannot stop, unlike normal ponies. If I did, normal ponies would not be able to see."

"'Tia, I am more than capable of raising your sun. You rose my moon for a thousand years. You could even ask Twilight Sparkle to replace you."

"Princess Twilight has her own duties. Nopony is going to replace me. They can't, and I refuse to stop until my very last breath..." She grunted, seeming pained.

The moon pony sighed. Even her magic was becoming too much for her...

She fired up her horn again, a faint blue light wrapping around the golden yellow one already encasing the fiery orb, it rising much faster now. Once it was placed properly, she released. "See? I can do it fine."

"You did nothing, you merely helped," Celestia mumbled.

Luna rolled her eyes and playfully slapped her forearm with a hoof. "Go to bed, 'Tia. The sun is up. Your job is done, now rest."
The mare raised an eyebrow "Luna, my work is...." and yawned, regrettably nodding. "...never done... but maybe you're right... Now that I think about it, I am really tired..."

"As I said. Now go. I will have Twilight fill your place today, you needn't worry."

"Who said I was worried? I have no doubts on Twilight's abilities. I know she'll do well."

Luna suddenly looked annoyed and Celestia laughed, rising to her hooves and turned. "Good morning, Luna. I'll see you sometime tonight." She smiled faintly, slowly and tiredly trudging to her chambers.

Luna held her smile until she disappeared, then her face fell. When would that mare learn that she couldn't hold up her destiny anymore? Was she really that stubborn? There were plenty of other ponies who could raise the sun in her place.

She huffed, standing up herself. "Maybe if she did not refuse an heir so much, we wouldn't be in this mess.." The night princess muttered to herself, trotting over to her throne and taking a seat.

It looked like she'd have to govern the day.

Again.