My hand hurts so I'll keep it short
Darkie was born achully into a normal family of pegasi. Her mother wanted an alicorn, so Darkie's dad wasnt a pegasi like her brother's, but what was thought to be a unicorn. Her 'dad' agreed on the alicorn plan. Her true dad was never seen.
So when she was born, it was a huge let down, a unicorn, or so they thought. She was rejected at first sight. Red, loving his newly born sister no matter what, said quote "If she gose, I go with her."
So thats what they did, both were shipped off to somewere they could have 'a second chance'

It was all bad luck.
Darkie never opened her eyes there, and Red was scared of everything. So of course they were rejected by everyone.
To the adults, they were nothing more than mouthes to feed. They left them, huddled together, alone in Everfree forest.
A dragon, a bit bidder than a pony, took them in. She was the one to name them. Dark Heart, for the misunderstood heart of dragons, and Red Break, for surviving his broken heart when his parents left him with no remorse.

Lets skip to were Darkie was seven.
In the middle of Everfree, she found a fawn. Having a heart, she went out of her way to raise it, naming the fawn, Fawna (how creative)
Then came the day that changed her.
While playing in a field with her, Fawna was shot by a hunter. In a fit of rage, the little black furball shot him back, now thats a bit morbid for a 7 year old no? If all poor little Darkie could do was watch her suffer, you might kiIl too.

Bla bla bla, decided to tame dragons to help others
Bla bla bla, brother works part time at sugar cube
Bla bla bla, got hoodie when she was sixteen
Bla bla bleh, got sword when she turned seven teen (July 13 2O13)
AAAAND BOOM