One morning, Twilight received a letter from The Crystal Empire.
It said: "Dear Twilight,
I need a favor from you and your friends. I am curious as to why Flurry was an alicorn when I gave birth to her. Can you please find an answer for me? That would be most sweet of you. Signed, Cadence"
Twilight knew what Cadence meant, and she gathered her friends.
"I think there might be an old book at Celestia and Luna's old castle with an answer to that.", said Rarity.
"I think you are right.", said Twilight in return.
So, they all began the journey to the ancient ruins of The Castle of The Two Sisters, not knowing what they would uncover.
"Hey Twi, why couldn't Neighsay come with us? He knows his way around libraries pretty well, if you think about the last time we were here.", asked Applejack as they neared the ruins of the giant castle.
"He broke his leg during their last rescue mission, so he is in the hospital.", Twilight answered.
They entered the age old castle, ripped tapestries hung in different spots, and some parts of the cracked ceiling were just waiting to fall down.
"Here is the library.", said Dash as they went in.
The books were covered with cobwebs, and dust, having not been touched for millennia. Fluttershy sneezed, as a puff of it landed in front of her.
"Let's split up, girls.", Twilight said, as they gathered in the middle of the giant library. "If anyone finds a possible source of an answer, radio the others.", she explained as she handed out two-way radios.
"Sure thing.", said Rainbow.
"Okay.", said Fluttershy.
"Alright Darling.", said Rarity.
"Okey dokey lokey.", said Pinkie.
"OK, let's do it y'all.", said Applejack.
They began searching in different parts of the library, in old editions, archives, history, mystical tales, tall tales, and many many more. Unfortunately, nopony could find a book regarding the birth of an alicorn. Suddenly, Rainbow called in.
"I think you better come look at this.", she said over the radio.
They came to where she was, but there was just a bookshelf.
"I swear I can feel a draft coming from behind here.", she whispered.
They listened closely, and could hear the air whistling behind the shelf too.
Twilight pulled on a book, but it clicked instead of sliding off the shelf. The shelf slid back to reveal a small chamber. They stepped inside, and onto an outlined portion of the floor. Then the section of the floor began to lower, and they realized they were on a hidden elevator platform.
"Where do you think this goes?" asked Fluttershy in a nervous manner.
"I have no idea, but we will find out.", said Twilight, trying to calm her down.
Minutes later, the platform ground to a halt, at the end of a long stone tunnel, still lit with flickering torches, after thousands of years. The torches made Twilight wonder as if they were enchanted to stay lit, but they proceeded to the other end, and found a massive set of ornate double doors. Opening the doors, they were shocked by what they saw. They were in a humongous room, full of ancient texts and books. Twilight could not believe her eyes.
They began to search eagerly for a book in the room that would hold an answer to Cadence's request. Finally, Rainbow spotted a well-worn book. Its front cover was studded with beautiful jewels, but the whole book was covered in a half-inch layer of dust, which she promptly blew off.
"AAACHOOO!!!", sneezed Twilight as it flew in her face.
"So sorry.", said Rainbow as she brought the book down for Twilight to look at.
"Equestria's Oldest Legends", said Twilight, reading the faded title on the jeweled book's leather cover.
"Do you think there is something in here that would answer Cadence's question?", Rarity asked.
"I hope so.", Twilight replied.
They found a title in the Table of Contents, that said "The Alicorn Legend", and Twilight became pumped, and turned straight to it.
"Way way back, many millennia ago...", Twilight started. " A beautiful alicorn named Queen Galaxia lived with her husband, King Cosmos as the highest rulers of what had recently become Equestria. They were happy with how everything was going. The pegasi, unicorns, and earth ponies were cooperating with one another successfully, and without conflict. Three weeks later, Galaxia had shocking news for her husband. "I'm pregnant, we're going to have a foal", she said to him. He smiled warmly, and kissed her happily. Nine months later, after loads of preparation for their new baby, Galaxia went into labor, and Cosmos rushed her to the hospital. She was in pain for a while, but they cried tears of happiness when they heard the first cry of life from their little one. She had a horn, and tiny wings on her soft white back. Her beautiful mane was pastel, and multicolored. It is unknown what they named her. Five years later, Galaxia told her daughter that she was going to be a big sister. The filly jumped for joy and kissed her mother. After nine months, she had tears of happiness in her eyes as she cradled her newborn sister in her hooves. Her sister was the color of night, and had a bluish-violet mane. The filly gave her sister the name of ... Luna."
Twilight and her friends were wide eyed.
"They were alicorns at birth?", Rainbow wondered aloud.
"There's more to it.", Twilight said. "Many years later, an alicorn princess who was married to a unicorn, lived far north in the early Crystal Empire. She soon gave birth to a filly, who looked like a unicorn at first glance, but soon sprouted wings just two minutes later. The filly was named Mi Amore Cadenza, and she became the first princess who had the power to spread love. From then on, the legend has been that if an alicorn princess is married to a unicorn, there is a 50/50 chance that each child they have, will be an alicorn at birth.
They also found two scrolls on a shelf. Twilight did not know what they were, but soon found out when Dash unrolled and examined them.
"These are Celestia and Luna's birth certificates.", said Rainbow, when she saw their parents' names written, and the pictures of Celestia and Luna as newborn fillies, sound asleep and wrapped in baby blankets.
"I can't believe it!!", exclaimed Twilight. "Celestia and Luna were born as alicorns, and Cadence became an alicorn two minutes after her birth."
Excited, the girls boarded the Friendship Express, and headed to the Crystal Empire.
"Cadence, you're not going to believe this.", shouted Twilight, when Cadence met them at the station. "You became an alicorn just two minutes after your birth.", she said as she handed the book to Cadence.
Cadence was overwhelmed to read that her own birth sparked a legend, and that it came true when she gave birth to Flurry Heart. She suspected that her anatomy was different, which explained why Flurry's wings were huge at her birth.
"I can not believe this!", Cadence cried. "My birth sparked a legend in Equestria, and I showed it to be true when I gave birth to my daughter." "THANK YOU!!", she yelled, and she hugged them all.
"We wouldn't mind staying for a while.", said Rainbow.
