The ascent of the sun above Canterlot brought with it the start of a brand new day for the citizens of Equestria. Ponies everywhere either retreated to their beds after finishing a gruelling night shift, or came back from the land of dreams to start another day.

But for one guard at the Castle, this meant a whole new day of cleaning the floors. He stared at the mop and bucket with disdain, trying in vain to pick it up in his forehooves. When the object fell out his grasp and landed on the floor, he cursed under his breath.

"Stupid mop," he grumbled, walking over and absent-mindedly kicking at it. "Whoever designed this damn thing clearly didn't have us pegasi in mind when they did. Who says that unicorns are the only ponies that clean stuff?" He picked up the mop with his teeth and dropped it in the bucket. "Screw it, I'm taking a break."

He put the bucket in a nearby cupboard and began trotting down the corridor humming to himself. As he walked, he looked out of the window at the sky above. The sun peeked out over the few clouds in the sky, bathing the horizon in a stunning orange glow.

"All hail Sunbutt," the guard smirked. "All hail Sunbutt and her magnificent sunny days."

"Why thank you, guard," a voice from behind him chimed. "It pleases me to know that everypony enjoys a good bit of sunshine every now and again." There was a pause. "Though I have to tell you that my name is 'Celestia', not 'Sunbutt.'"

Instead of turning to face her, as she expected, the guard immediately went rigid with fear. "As if using that name in front of Princess Twilight wasn't bad enough," he groaned. "Now I've went and used it in front of the very pony it belongs to." He spun around on the spot and bowed. "My most sincere apologies, Your Highness, I meant absolutely no offence by it!"

Celestia chuckled. "No offence was taken, my little pony," she replied. "It is common knowledge around the guards of Luna's little nickname for me, but you are the first guard I've met to actually use it in everyday conversation — even if that conversation is actually meant to be with yourself." She smirked. "And now it would seem that Twilight knows of the name as well. Tell me, guard, what did you tell her exactly?"

"I told her to speak with Princess Luna," the guard replied. "As it was because of her your, er, 'nickname' was revealed."

"And this happened last night, yes?" Celestia asked, to which the guard nodded. "Then Twilight will already know the story of how I got that name to begin with... something I'm sure my dear sister took great delight in." She paused for a moment. "Thank you for your time, guard, you may return to your duties. If you'll excuse me, I believe Twilight is due to hear another story. After all, Luna isn't the only one with an embarrassing nickname." She began to walk away, but stopped. "I completely forgot my manners... what is your name, my little pony? You're not in any trouble, I would just like to be able to call you something other than 'guard.'"

"Flash Sentry, Princess," he replied. "My name is Flash Sentry." Celestia nodded and walked away, leaving Flash to sit on his haunches and sigh. "Oh well, at least I can take solace in the fact my mouth didn't get me into any more trouble..."

Celestia walked up to a door with Twilight's cutie mark on the handle, and knocked on it gently. A few moments passed before Twilight finally answered. "Good morning, Celestia," she said. "What brings you to my chambers so early?"

"I was wondering if I could talk to you," Celestia replied. "Might I come in for a moment?"

Twilight nodded. "But of course," she said. "Please, go right ahead."

Celestia dipped her head in thanks and trotted into the room. The floor was littered with books about princesses and a desk near the window was piled so high with parchment, only a tiny sliver of sunlight was making it through. Giggling sheepishly, Twilight cleared some space, allowing the sun to shine freely while Celestia watched with a bemused expression on her face.

"So, uh..." Twilight began, sitting in front of an ornate marble fireplace which was alive with a roaring flame. "What did you want to talk to me about?"

"I wanted to talk to you about 'Sunbutt,'" Celestia said, to which Twilight gasped and looked away. "Don't worry, Twilight, I am not angry with you for knowing. I'm just wondering... did Luna tell you the story of how I got my cutie mark and this nickname?"

"She did," Twilight nodded. "But I promise I won't tell anypony how it happened — that is one secret I will take to my grave."

Celestia chuckled heartily. "Did you know, Twilight, that Luna also has a nickname?" Twilight shook her head. "In that case, fellow Princess, I believe it is time you learned about I came to refer to my dear sister Luna as 'Moonbutt.'"

One Thousand, Five Hundred and Sixty-Nine Years Ago...

"— and so, it is with great sadness that I commit the bodies of our beloved Queen Galaxia and King Hyperion to the earth," spoke a unicorn mare wearing a black jacket. "May they find the everlasting peace they deserve in the afterlife." She turned to the two alicorns nearby. "Princess Celestia, Princess Luna, would either of you like to say a few words about your parents?"

Celestia nodded solemnly and stepped up to the podium, the unicorn stepping aside with a small bow. She looked out over the crowd of mourners and sighed.

"Much of what I wanted to say has already been said," she lamented. "Galaxia and Hyperion were wise and benevolent rulers, this is true, but they were also loving and caring parents. We all knew that this day would come – but not so soon – and they spent every moment they could preparing Luna and I to take over. I for one promise to perform my new duties with the same level of compassion and dedication that they showed, and I hope that their memories live on forever." She looked over to Luna, who shook her head forcefully. "My sister does not wish to speak, but I know that she shares the same feelings I do."

She stepped down from the podium and walked over to Luna, wrapping her wings around the other alicorn in a tight hug. As the two siblings watched, the coffins were lowered into the ground — a sight Luna could not take. Sobbing profusely, she fled the area, leaving a sombre Celestia behind.

Celestia wiped the stray tears from her eyes as Twilight spoke. "If you don't mind me asking, Celestia," she said. "How... how did..."

"How did my parents die?" Celestia finished. "Well, do you remember how, when she was telling you my story, Luna mentioned that our parents went to Gryphus?"

"She did," Twilight replied. "She said that they were attending a ceremony to mark the hundredth anniversary of the treaty which ended the war between ponies and gryphons."

Celestia's eyes misted over and she hung her head. "On the way back..." she choked. "On the way back, they were caught up in a horrendous storm. Their chariot crashed and they, along with the pegasi pulling it, were killed instantly."

"Oh, Celestia," Twilight gasped, hugging her. "I'm so sorry... I'm guessing you and Luna coped as best you could?"

"We did," Celestia sniffled. "We were only teenagers, and suddenly we found ourselves to be in permanent charge. We weren't ready, and we both had to grow up so fast — but sadly, our methods of 'coping' were both completely different..."

Celestia woke up with a start, scattering several pieces of parchment across the floor. She wiped her eyes and looked around the room groggily, smacking her dry lips together. She stretched languidly and walked into her bathroom, stopping at the sink and filling a glass with water. Taking a few sips, she sighed wistfully and put a forehoof to her temple.

"I've been working far too much lately," she said to herself. "All this paperwork... I don't know how mother coped." She finished the water and put the glass down. "I need to go and find Luna, given that we haven't talked much since the funeral."

After a quick wash, Celestia left her room and walked a few paces down the hall. She knocked on the door a couple of times, waiting patiently for a reply.

"By the Creator, go away!" Luna shouted. "I specifically said that I was not to be disturbed! What part of that did you not under—"

"Lulu, it's me," Celestia interrupted, before sighing. "I'm worried about you, sister. I have barely seen you in these last two weeks, and when I have you do your best to avoid me. Please, let me in so that we can talk."

There was a pause before Luna replied. "And what good what that do?" she demanded, her words slurred. "Mother and Father are both dead, Tia, and no amount of talking will bring them back! You know as well as I do that we are not ready to lead Equestria, so why are we even bothering to try?!"

"H-have you been drinking, Luna?" Celestia asked worriedly, grabbing the door handle. There was no reply, so she turned the knob. "Have it your way then, Lulu, I'm coming in."

She opened the door and stepped inside, her nose immediately being assaulted by the overpowering stench of alcohol. Luna lay in the middle of the floor, holding up a forehoof in a futile attempt to cover her eyes from the light Celestia's entrance had allowed in.

"Go away," she croaked, sitting upright and waving a bottle of scotch around. "Leave me, Tia. Leave me to my grief." She took a swig from the bottle. "I just can't stand the idea of them not being around anymore, sister. I miss them so much."

Celestia took the bottle from Luna and tossed it to one side, shattering the glass and spilling the contents over the floor. Before Luna could react, she had wrapped her up in a hug. "I know you are grieving, Lulu," she whispered. "But this is not the way to go about it. You should try talking to somepony, as it would help you a lot better than alcohol ever could."

"Says the one who has spent nearly every waking moment buried under paperwork," Luna sneered. "Tell me, Tia, have you actually tried practising what you're preaching?"

"I meant you could try talking to me," Celestia replied. "I love you, Luna, and I hate seeing you like this." She paused for a moment. "And we both know that mother and father would hate it too."

Luna pushed Celestia away, a low growl escaping her throat. "Well they're both dead," she snapped. "So pardon me for not really caring about what they might think."

The sound of a slap filled the air as Celestia brought her forehoof across Luna's face. "How can you be so callous?" she hissed. "I know they're dead, Lulu, because we were at their funeral! And now we've got no choice but to take control of the responsibilities that have been entrusted to us!" She placed her forehooves on Luna's shoulders. "You need to grow up, sister, and help me to maintain control of our destinies!"

Luna rubbed her cheek for a moment, then shook her head fiercely and ran to a nearby window. "No!" she yelled, opening it. "Leave me alone, Tia, I'm not ready to accept this!"

With those words, she spread her wings and flew out of the window, leaving Celestia standing in her bedroom with tears flowing freely down both cheeks.

"She was drunk?" Twilight asked, aghast. "Pardon me for saying, Celestia, but I think you're telling me the wrong story."

Celestia shook her head. "No, Twilight," she replied. "This is indeed the story of how Luna came to be known as 'Moonbutt' — these events merely helped contribute to her acquisition of the name." She sighed. "But I do regret slapping her... I guess at the time I thought it would make her see sense."

"Neither of you was ready for this," Twilight soothed. "I can't blame either of you for doing the things you did."

"Thank you, Twilight," Celestia said. "Now, where was I?"

The next morning brought with it an urgent knocking on Celestia's bedroom door. She rolled out of bed and trudged over, yanking the door open with her magic to reveal an out-of-breath guard. "What is it?" she asked curtly, looking out the window at the night sky. "Can't you see that it is still dark outside?"

"That's the thing, Your Highness," the guard panted. "It is actually eight o' clock in the morning — but Princess Luna is yet to lower the moon. And when we searched her chambers... she was gone."

Celestia gasped. "She didn't come back?" she asked. The guard looked at her in bewilderment. "We had a... disagreement last night, and she went out for an evening flight to cool down. I think I know where she went, so I will go out to look for her. In the meantime, tell anypony who asks that Luna is busy with matters of state. I do not, under any circumstances, want a panic. Clear?"

The guard saluted. "Yes, Your Highness," he replied. "It will be done." He then turned tail and galloped down the corridor.

Celestia opened her bedroom window and immediately took to the sky. "I hope you're all right, Luna," she said. "I don't want to lose anypony else close to me."

Celestia landed gracefully on the harsh rock and looked around. "Luna?" she called. "Luna, are you out here?" The only response she got was a muffled cry which made the blood in her veins go cold. "Luna? Luna! Hang on, sister, I'm coming! Just keep shouting, and I'll follow your voice!"

Luna kept shouting, her voice still muffled by means unknown, and Celestia followed dutifully. She soon came across a small crater and peered into it — her eyes soon falling on, and then widening at, the peculiar sight which lay ahead.

"Tia?" Luna asked. "Is that you? Please, gods, say it is."

"It's me, Lulu," Celestia said, stifling a giggle. "But... how on Equestria did you get yourself into this mess?"

"I came here to think, as this place is always peaceful," Luna grunted. "But have you ever tried flying drunk? It's not as easy as you think — which is why I lost control and crashed."

"Are you all right?" Celestia queried. "Do... do you need any help?"

"What do you think?" Luna shouted. "Get me out of this stupid thing already! I'm hungry, thirsty and I want to go home!"

Celestia took a step towards the crater — and the alicorn who was stuck in the middle of it. Only Luna's flanks and hind legs, which were kicking fiercely, could be seen protruding from it. Charging her horn, Celestia summoned a blast of energy which turned the small crater into a much bigger one, thus freeing Luna from her prison.

"Thank you," Luna said as she stood up and dusted herself off. Both sisters stood in silence for a moment before Luna sighed. "I'm sorry, Tia. I never meant what I said last night, honestly, it's just that... I'm scared about what the future might hold."

Celestia wrapped her wings around Luna, pulling her in for a hug. "And I'm sorry for slapping you," she replied. "I know how you must feel — mother and father both pass on, leaving us with all of this responsibility, and neither of us knows how to cope without them being here to guide us."

"That is why I'm scared," Luna replied. "Because they're not here anymore. But... as long as we're together, we can face whatever comes our way. Right?" Celestia nodded. "Right, well... in that case, I think I'm ready to go home and face my responsibilities. I'm sure that half of Equestria is in a blind panic by now because I haven't been able to lower this thing yet."

She took off, followed by Celestia, and together the two of them began the journey home. As Canterlot Castle came into view, Celestia stopped and hovered, casting her gaze over the spires.

"It is all ours," she said solemnly. "All of it. Mother and father spent many years preparing us for this moment, and I want to make them proud. Can I rely on your support, Lulu?"

"You can," Luna replied. "While I was trapped in that crater, I had a lot of time to think. Once the alcohol wore off and the hangover set in, I realised just how foolish I had been. You're right, Tia, mother and father did spend many years preparing us for this — it would an affront to their memories if I was to throw all of that away because of my own personal misgivings." Determination flashed before her eyes. "Come, Tia, let us return home and become the rulers we were born to be."

Celestia grinned. "Lead the way, Moonbutt," she said, prompting Luna to turn and stare at her. "Oh, did I not say? After seeing your flank sticking out the moon like that, I felt you needed a change of name. Do you like it?"

"Why yes, Sunbutt," Luna replied. "I do like it."

With that, the two of them resumed their flight, their giggles carrying on the cool morning air.

"And that's how Luna got the nickname 'Moonbutt,'" Celestia said, smiling fondly at the memory. "Given the circumstances in which she got it, I'm sure you can understand why we rarely use it."

Twilight nodded. "I understand," she replied. "But I'm glad to see that the two of you put aside your fears and made Equestria what it is today. Your parents would be proud of you both."

"You're right, Twilight," Celestia said, nuzzling the younger alicorn's cheek. "They would be proud, of that I have no doubt." She ended the nuzzle and stood up, stretching her legs and wings. "Thank you for listening to my story — but just like Luna, I must ask you to keep what you have learned a secret."

"Of course, Celestia," Twilight replied, standing up and opening the door with her magic. "You have my word. In the meantime..." Her stomach gurgled violently. "Shall we go to breakfast?"

"Breakfast sounds lovely," Celestia said. "Perhaps we can catch Luna there before she goes to bed — it has been a while since the three of us talked together."

With those words the two alicorns extinguished the lights and left the room, closing the door behind them. As they walked down the corridor, neither of them noticed a pony peeking out of a cupboard.

"So Luna is called 'Moonbutt', eh?" he said to himself. He paused before he hit himself with a forehoof. "No, Flash, don't go there. You already know way too much as it is."

He sighed wistfully and picked up his mop before resuming his scrubbing, his own cheerful whistling breaking the otherwise still silence of the magnificent halls.

Author's Notes:

And now you know. Apologies if you found this to be a bit more feels-y than its predecessor, but I wanted to try something else with this. Let me know what you think!

This is dedicated to everyone who requested a sequel to The Origin Of Sunbutt.

Why was Flash Sentry mopping the floor?

To answer this, I would like to quote a comment — left by Neko Majin C on the previous story:

Thank you for your time, guard, you may return to... whatever it was you were doing.

Some princess, she does not even take the time to learn the guard's name. "Return to your mopping, Insignificant Redshirt." (That is the guards name.)

It is because of this comment that the previously unnamed guard, whom Twilight learned Celestia's nickname from, made his appearance in this story. And since I'm not a huge fan of Flash Sentry... why not give him mopping duty?