A Sun's Secret

by Diamond_Emblem

Rating: everyone
Tags: Sunset Shimmer, Slice of Life, My Little Pony: Friendship is Magic, Sad, Princess Luna, Princess Celestia
Length: 3709

Celestia doesn't seem well these days. Luna decides she needs to have a talk with her sister to find out what's been bothering her. The reason why will change Luna's world.

Something's been on Celestia's mind these days. Luna can tell by the way her sister is acting, something isn't right. But is Luna prepared for the truth that her sister has been hiding for years?

Permission to use artwork from BreezyBlueYT on Deviantart, thanks a bunch!
Check out the previous version here!

Published 2016-04-29 00:00:01 UTC
Last updated 2019-08-04 00:12:08 UTC

Chapter One

The Only Chapter

"Steady now..."

Princess Luna lifted the moon to the exact location it needed to be located at. With her powerful alicorn magic, she managed with little difficulty. It was another Equestrian night that Luna had to take care of. The stars were perfectly aligned where they needed to be. They glimmered and sparkled, brightening the vast dark sky. The seemingly tiny lights on the streets of Canterlot were lit up on the Saturday night. Luna knew several Canterlotians were on their way to a "club," to perhaps drown themselves in debt or cider. It had become normal for Princess Luna to learn of these weekly antics.

Yet something seemed off.

Maybe it was her stomach, after having a sip of the soup she had tried to create, which had tasted like shriveled carrots and burnt wheat. Or the strange white horseshoes that seemed to be quote-unquote, "trending" everywhere. But it was most likely Luna's sister, Princess Celestia, who was strange that day.

Tia was already strange on her own. She preferred to eat cake in private and drank several cups of tea a day. She spiced up the gala by inviting guests that could create chaos and nearly destroyed the gala. Later, Celestia would say the gala had been spectacular.

However, the entire day, Celestia had been acting very peculiar. Luna noticed Tia had barely been listening to the Equestrian reports one of the Royal Guards had been reading off to the both during the morning. Celestia had barely eaten more than a nibble of cake the entire day. Most of the time, she was distracted and off-focus. If Luna needed Celestia's attention, she would have to begin to raise the moon.

Princess Luna double-checked the sky to see if any star or constellation was out of place. In reality, she was staring at the sky as if it could give her answers to why Celestia seemed gloomy.

The princess of the night sighed. She needed answers. If not for Luna's curiosity and concern, then for Celestia's well-being to serve Equestria. Tia could not be distracted. Luna couldn't rule Equestria alone, even if her sister had done it.

Princess Luna glanced one last time at the night sky. She sighed and entered the tower to rest for the night.

The sky-tall tower had a long spiral staircase that ended on the fourth floor of the Canterlot Castle. The fourth floor was where Princess Celestia and Princess Luna slept, and had their own rooms for activities such as writing, reading, sunbathing, moon bathing, and so on. However, Luna preferred to spend her free time catching up with the modern days of Equestria.

Luna trotted down the stairs, enjoying the echoes of her hoovesteps in the quiet tower. Every few feet, there was a window that let the moonlight stream inside, giving Princess Luna the light she needed to find her way through the dark.

At the bottom of the staircase, Luna headed to the east wing of the castle. The castle was dark and quiet, except for the occasional sight of a Royal Guard. When one passed by, Luna acknowledged them by nodding. The Royal Guard always nodded back.

Luna passed several rooms but knew none belonged to Celestia. If it was the last thing Luna did, she would find out what was going on with her sister.

She reached the end of the hallway. Princess Luna's muzzle scrunched up. She knew where Tia's room was located, but how could she not have found it yet? Perhaps the night was making it too difficult to see. Or maybe the thoughts swimming in Luna's head was making it difficult to concentrate on finding Celestia's room.

Luna turned and went back to search for Celestia's room. Certainly Tia would already be sleeping; she always slept in when it was Luna's turn to take care of Equestria. It was around one in the morning. Surely Celestia would be sleeping. Princess Luna was never tired at night and took several naps during the day.

Suddenly Luna's ears perked up. She heard something incredibly out of the ordinary.

Crying. It was soft crying, as if the pony that was doing it didn't want anypony else to listen.

The crying sounded like it belonged to Celestia.

Luna quietly walked back and looked around. The crying seemed to be coming from her left. She looked at the cracks that were under the doors.

The crying became louder. Luna suddenly noticed one of the cracks let out a dim light.

Luna looked up. She recognized it as Celestia's old room, the one she slept in before deciding to move into a new, better bedroom.

Princess Luna opened the door very quietly with her magic, opening a crack large enough for Luna to poke her head inside.

She looked inside. She nearly gasped when she saw Princess Celestia sobbing into a pillow on the purple carpet. Several pieces of parchment were scattered in the room. The fireplace was lit with a small blaze. A candle was lit next to Celestia. An old wooden box with several golden and red etchings on it was open beside the fireplace.

"Sister?" Luna spoke softly.

Celestia's head shot up. She immediately became silent. She appeared to move her hooves so she could wipe away tears that had fallen onto her cheeks and ones that were still in her eyes.

Tia turned to face Luna. "Oh, Luna," Celestia said casually. "It's a lovely night you've created, isn't it?"

Luna could see the ghost marks of tears on Celestia's cheeks. Her sister's eyes were slightly red. Her eyes carried an incredibly heavy solemness. Celestia tried to pretend everything was natural with a small smile and a regal posture.

"Celestia, take off that fake smile," Luna said curtly. She walked towards her sister. "I heard you crying and came to investigate. What's wrong, Tia?"

Celestia chuckled lightly and said, "Nothing. I was merely reading some of Twilight Sparkle's old lessons of friendship." She beckoned her head towards the chest. "A year has certainly passed quicker than I would have imagined."

"Celeste, that's enough," Luna said sternly. "You have been acting incredibly peculiar all day. You barely paid attention to the daily reports and you let your tea get cold. You went to bed early today, but right now you're awake! If that wasn't enough, you're crying at one in the morning and pretending everything's alright!"

"And everything is alright," Celestia said calmly. Her voice seemed to shake. "I'll go back to bed in a moment, Woona. How about you go to sleep? It'll do you some good."

"Celestia, I am not going to leave this room until you tell me what you are so upset about!" Luna said. She glared at her sister with a look that Tia knew she had to fess up.

Yet she persisted. "Luna, I am fine. Don't worry about me," Celestia said. A tear slid down her face.

"You're crying!" Luna said. "Yet you continue to claim you are not upset."

"It's because I'm not," Celestia said.

"Then explain to me why you are crying!"

"I get a little emotional sometimes."

"You are not fooling me, sister."

"Please, Luna, just go to bed."

Luna sighed, exasperated. "Celeste, I'm your sister," she said. "You haven't kept any secrets from me, besides the one you are currently refusing to tell me, and I haven't kept any secrets from you. I care about you. I know you're not alright. And I'm going to keep on worrying about you until you tell me why you were crying."

Luna held firm and stern as her sister read her expression. After a minute, the princess of the sun finally sighed. "Alright, Luna," she said. "Close the door behind you."

She did as Celestia told and quietly closed the door. Tia cast a spell on the walls that Luna recognized as a soundproof spell.

"Take a seat if you would like," Celestia said in a shaky voice.

Luna made herself at home and sat beside her sister. She could smell the candle that was burning; it smelt like the coziness of a campfire with family. She glanced at one of the papers and saw they were beginning to yellow. More interesting enough, the writing on the parchment did not belong to Princess Twilight; it belonged to somepony else.

"Luna..." Celestia swallowed hard as another tear fell. "You remember the story I told you about Sunset Shimmer, correct?"

"Of course, sister," Luna replied.

Celestia repeated it anyway. "Sunset Shimmer was one of my students in my school before Twilight Sparkle began attending. She was an excellent student, a prodigy of magic just like Twilight. However, she never understood humility like Twilight did. When I showed her the mirror, Sunset saw herself as an alicorn, a princess of Equestria. She became obsessed with the mirror and the future of her as a princess. She disobeyed my pleading and sneaked behind my back to get to the portal. I had to expel her. Then, she escaped into the other world."

She sighed. "From the other world, she wrote to me from a notebook I had gifted her. I always loved her letters." She beckoned to the parchment lying on the ground. "Those were all her the messages we shared."

"But Twilight Sparkle has your notebook now, does she not?" Luna asked.

Celestia nodded. "But yesterday, she sent me the notebook and told me Sunset Shimmer wanted to write to me. We...we wrote to each other the other day. She wrote..." Celestia swallowed hard. Her tears were coming faster. "She said I was always like a mother to her."

Luna nodded but didn't quite understand what the problem was. "And that is a bad thing?" she asked.

"Luna...I'm going to tell you something you must never tell anypony else," Celestia said.

"Of course, sister," Luna said. "I will guard your secret with my life." She felt incredibly nervous. A secret that Celestia hid from Luna? Unheard of. It was most likely a huge secret that would change everything.

"Luna..." Celestia took a deep, shaky breath. "Sunset Shimmer is my daughter."

Time seemed to freeze. The world seemed to shatter. Luna's heart nearly stopped. She didn't know how she felt. Was she upset for Celestia not telling her? Or enraged that Celestia never told her? Betrayed. Out of everything, Luna felt betrayed. How could Celestia not have told something as important as a Royal Daughter? Why would she keep this secret from her own sister?

Luna needed answers. And she was determined to get them.

"Wha----Dau----" Luna glared at the Celestia and immediately stood. "WHO IS THE STALLION THAT IS RESPONSIBLE FOR THIS?!"

"Luna, please calm down," Celestia pleaded. Tears were streaming down her face rapidly. "I guess the soundproof spell truly was a good idea."

"BUT YOU?! YOU GAVE BIRTH TO SUNSET SHIMMER?!" Luna yelled in her royal Canterlot voice.

"Yes, but it's not what you think----"

"NO, SISTER!"" Luna yelled. "YOU MUST TELL ME EVERYTHING!"

"And I was planning to," Celestia said, sniffling. "Please calm down, Luna. Then I'll answer any questions you have. Calm down, sister."

Luna still felt like nothing was right, nothing was okay. But she sat back down and let a few tears out. For her sister.

"Are you calm now?" Celestia asked.

Luna nodded. "Who...when..." She shook her head. "How did this all begin?"

Celestia took a deep breath. "It all began a few years back. I was practicing the Shape-Shifting spell. I wanted to be a common mare for a day. I had been feeling particularly lonely that day. I wanted to be carefree and have fun like we had when we were little fillies. The day was going so well, until...I met Flame Luster. Had I been younger, I would have stayed with him. He was everything I could possibly dream of in a stallion! Red mane, yellow coat, hypnotizing bright blue eyes. He was kind, amazing, charming, funny. He fell for me the moment we met. I spent the rest of my day with him. I...told him that I couldn't stay with him when he asked if we could be together. He was fine with it, perhaps a little heartbroken. But he asked if...we could spend the night together and after I could leave. The foolish mare I was, I accepted."

Luna understood Celestia's message. "What happened afterward?" she asked.

"I returned to the throne the next morning as if nothing were wrong." Celestia swallowed. "But after a few days, I didn't feel quite well. I was vomiting and sometimes I had the sudden desire to eat more than I would usually eat in a day. I knew something was wrong. I performed a spell that would tell me if I was with a foal. Turned out, we weren't careful enough. For the rest of the nine months, I used a cloaking spell to hide my form. I was careful in sneaking in as much food as I could without raising suspicion. In the ninth month, it was the middle of the night when I went through labor. I used the same soundproof spell and fetched a midmare. The one pony besides you that I could trust. Twilight Velvet."

Luna's eyes widened. "Twilight Velvet?" she repeated. "The mother of Twilight Sparkle?"

Celestia nodded. "I trusted her with this secret, and still do. When Sunset Shimmer was born, I knew I could not keep her. For as much as I didn't want to let go of the daughter I had just met, I needed to. The next morning, I told a Royal Guard that I found Sunset Shimmer in the night, in my room. I told him I knew of a stallion who would make a wonderful father. I told him to find Flame Luster. Before the guard left with my baby, I snuck a letter into the basket she was in. I wrote that this was his daughter, Sunset Shimmer, and I was the mare he had met months ago, Imperia Light. I wrote that I couldn't take care of Sunset because my mother forbade me to keep her. I wrote how I asked a Royal Guard to take Sunset to him. Years later, Sunset Shimmer is accepted into my school. And in the time we had together, I made sure she was as close to me as possible. She has no idea I am her mother, and only knows I had to give her up. It broke my heart when I had to expel my own daughter. I could no longer be with her, once again. And I still cannot. It ached, knowing my daughter hated me and left to another world without knowing how much I truly love her."

"Are you going to tell Sunset Shimmer the truth?" Luna asked.

"I don't know," Celestia confessed. "I want to, so she can come home and I can finally, truly get to know my daughter. But I'm terrified. First, she might hate me and ask questions or something far worse. Also, she's made such good friends in the other world. It's like a fresh start. Moreover, the secret could get out and chaos would erupt."

"But she's your daughter," Luna said. "She deserves to know you love her."

"I know. But the truth is a dangerous thing to play with," Celestia said.

"Are you...Has Flame Luster contacted you ever since?" Luna asked.

"No. I will most likely never receive any of his letters if he tried to contact me. Imperia Light does not exist. Celestia does." The princess of the day sniffled. "I fell for a stallion I shouldn't have. I had a daughter that I cannot openly love."

"What would happen if Sunset found out?"

"I doubt she would. She's in the other world now. The only ponies who know about Sunset are Twilight Velvet, you, and I," Celestia said. "And I know my secret is safe with you."

Luna blinked back a fresh round of tears. "You miss Sunset, don't you," she said.

"Very much," Celestia said. She wiped a few of tears away to make room for more. "Luna, the ache I feel in my heart is killing me. It destroyed me when I had to give her up. I should be able to care about Sunset, worry about her, and be with her. She's my daughter. She's fifteen years old, and I didn't have the chance to watch her grow up."

"Sister, you deserve to be able to cherish your daughter, get to truly know her," Luna said. "After a thousand years of ruling Equestria, you've been lonely without me. I wish you would have told me sooner."

"I couldn't," Celestia whispered. "At the time you came back, the one pony on my mind was you, and that you were finally free. Because of something I did."

"It was completely necessary," Luna said. The heartache of the banishment no longer lingered after she got rid of the Tantabus. Luna had forgiven her sister for punishing her.

"Just like giving Sunset away was." Celestia looked down at one of the parchments. One of her tears dropped onto it.

Luna glared silently down at the parchment. It wasn't fair. Celestia gave birth to her daughter and then sent her off. Five years later, Celestia finally gets to know her daughter better, but Sunset had no idea it was Celestia who was her mother. She had believed the princess was keeping her from her destiny and run away to another world. Sunset didn't know the heartache Celestia had gone through in the past years. Sunset had grown up without the love of her mother, which was most likely the thing that impacted Sunset to become the mare she did. Now, Sunset was in another world, a world apart from the mother she never knew existed. More heartbreaking, Flame Luster no longer knew what happened to his daughter.

"You must tell Sunset, sister," Luna said.

Celestia shook her head. "As much as I want to tell her, it isn't possible. Everything will change for her, and it will be too fast and sudden. She'll ask too many questions, and perhaps try to find her father to ask questions that he cannot answer."

"I don't want you going through this heartache anymore," Luna said firmly, a waterfall of tears falling onto the carpet. "You will tell Sunset. You must. So you get to know the daughter you never raised, and I can meet my niece."

"Luna, I cannot."

"You have to! It isn't fair Sunset grew up without a mother when she can finally have one now, especially since she no longer hates you, and finds you as a mother!"

"I can't."

"What do you mean you can't?! You are Sunset's mother, and Sunset deserves to know who her mother is now that she has redeemed herself!"

"I can't!" Celestia sobbed. "Sunset will hate me for giving her up! She'll hate me for not telling her! She'll hate me for not being the mother she needed!"

It broke Luna's heart, watching Celestia cry because of the possibilities of hatred from Sunset to her mother. Luna couldn't stand to see her sister in tears. The last time she had seen Celestia cry was when the two had finally reunited on the 1,000 Summer Sun Celebration.

Luna was silent for a few minutes as Celestia sobbed into her pillow. The princess of the night wrapped a wing around her sister.

"You will never know until you tell her, sister," Luna said quietly.

Celestia sniffled. "B-But how?" she asked. "Something like this...I don't want to tell her through a book."

"You won't," Luna assured her. "You can ask Sunset through the book to visit Equestria for a few weeks. In of those weeks, you can get together with Sunset and finally tell her that you're her mother."

"What if she doesn't want to leave the other world?" Celestia asked doubtfully.

"Stop being so negative, Tia!" Luna said. "She'll want to finally reconcile with you after years of living in the other world without apologizing."

"She wrote to me, apologizing," Celestia said, sniffling.

Luna shook her head. "Sometimes words that are on paper cannot compare to words that are spoken," she said.

"Why do you want me to tell Sunset so badly?" Celestia asked.

Luna sighed. She didn't really know. She should have been furious that Celestia had disobeyed the Royal Laws. Now, Luna wanted Celestia to tell her daughter the truth. Suddenly she realized why Sunset Shimmer was such a big deal.

"Sunset is the first Royal Daughter," Luna said. "She is also my Royal Niece. Knowing I have a niece...I want to meet her. I want to know here as much as you do. And the heartache you're suffering, I want it to stop. I want you to be happy, Celeste. I care too much about you to let you suffer. And Sunset is also suffering. Perhaps you two could finally be the mother and daughter you two need each other to be."

Celestia let out a small smile. "You do care too much," she whispered.

Luna smiled. She summoned a box of tissues with her magic and passed it to her sister. "I do and I forever will," Luna said. She grabbed some tissues and wiped away her tears.

Celestia took a few tissues and cleaned her face. "Than you for the confidence, Luna," she said quietly.

"Of course, sister," Luna said. "Anything for you."

Luna tucked herself into Celestia's warmth and closed her wings. She put down the box of tissues and placed her tissues into a waste basket. "So when will you tell her?" Luna asked.

"In a few weeks, perhaps," Celestia mused. "I've wanted to tell her for so long."

"You've waited to tell her for fifteen years," Luna said. "I think you can wait another few weeks."

Luna sensed Celestia smile. "I'm glad I finally told you about Sunset," she said. "Love you, Luna."

"Love you too, sister."

Luna closed her eyes and focused on Celestia's breathing. The warmth from her sister and the fireplace made Luna sleepy. The idea of finally meeting her niece comforted Luna. Before she knew it, she was asleep with her sister.