Thirteen years ago
It's late at night and it is pouring rain outside of the Ponyville orphanage. A hooded mare stands under a large tree with a small bundle engulfed in her blue magic. She keeps looking back between the orphanage and small foal in front of her. It is a colt with a dark blue coat, a small tuft of a black mane with small streaks of light green and a small horn. He is only a few days old and the mare wanted to keep him in her embrace forever.
"I do not know if I can do this. He is my child and I love him. I wish to take care of him," said the mare in a desperate tone.
A caring, yet strong voice comes from a nearby alley, "You know you can not do that. I understand your love him, but your responsibilities are too great and of too many to take care of a foal."
"You cannot possibly understand! He is the only thing I have left of the one I loved!" The hooded mare yells at the source of the voice. The foal stirs at the sudden increase in volume. Noticing this, his mother begins to gently rock him back and forth whilst humming a soothing melody. He quickly calms back down.
"You know what must be done," says the voice in a more commanding tone. The mare sighs and nods her head in agreement. Shielding the foal from the rain, she trots up to the orphanage and sets the foal down in front of the door. She places a small box the size of an apple and two letters beside him.
She knocks on the door three times, then runs back behind the tree just as the door creaks open. An orange unicorn mare with a curly pink mane pokes her head through and sees the small colt, the box, and the letters. She levitates the letters up to eye level and sees one addressed to the runner of the orphanage, and the other is addressed to somepony named "Aurorus".
"I don't know anypony named Aurorus, so this must be for you," she says in a in a cheery, yet tired voice. She levitates the foal and the other items into the orphanage and follows them in.
The hooded mare watches as her foal is carried into the building. She turns around to find a tall figure standing behind her. She is startled at first, but quickly recognizes this pony and composes herself.
"Shall we be off then?" Asks the tall figure in its original caring voice.
"Yes. Let's go. I do not want to be here anymore," said the hooded mare with a heavy sigh. With the glow of a horn and a small flash, they’re gone.
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The orange mare looks at the young colt and sighs. "Poor little guy. I don't know why you were put here, but I will do my best to make it at least a good home for you," she says with a weak smile.
She sets him down in a small crib in the nursery and goes off to do his paperwork. When she reaches her desk she takes a look at the items that were dropped off with him. There are two well written letters, one addressed to her and one addressed to Aurorus. She opens her letter and reads it.
Dear Sunny Day,
I cannot take care of this young colt and wish for him to stay here at the Ponyville orphanage, as much as it pains me to do so. I ask that he is taken of and that he is as happy as he can be.
He was born on the twenty-eighth of last month. I say this so you have an accurate date of birth for him. On his thirteenth birthday, I ask you to give him the letter addressed to him and the small box. The box contains one last gift from me.
Please do not try to open the box or letter, because I have placed a strong protective ward on them that can only be broken with his magic.
Thank you for your time and please take good care of my little boy.
-Anonymous
After reading the letter, the mare examines it and box and senses the wards that were placed on them. She is impressed at their power. She places the items in the small safe under her desk and proceeds to fill out the paperwork for the new foal.
A small pair of eyes stare into Sunny's office with curiosity. The small filly who was the owner of said eyes sits there for a few minutes before hearing the mare mutter something about how much paperwork was involved in taking in a new foal. Her eyes widen at the words "new foal" and she dashes to the nursery.
She looks into each of the cribs searching for an unfamiliar face. She quickly finds his crib and looks inside to see a now awake foal. She stares into his emerald green eyes and says, "Hi there little guy. My name is Scootaloo, what's yours?"