Witch Boy

"Sorry, but it's for the better" Renaud read the letter for the umpth time, he knew Etienne well and that he didn't do it for the woman he called mom. No. But for him. For Lisa and _________. He seemed to forget the little girl that made Etienne's day better. It doesn't matter. What matters now is that he somehow works out how to communicate with his little brother. That's all.
Etienne.
That's his name. He doesn't have a specific surname. So it's just Etienne. He lives in a world where witches, fairies, vampires, werewolves, and all these supernatural beings live in equilibrium within the human race. There's only one fundamental rule. Don't. Mix. Race. That is only permitted with Humans none other. Werewolves can't mix with vampires, witches or any other race but humans or their own - and that is inputted with all the other races. Anyone who does is permitted a significant penalty and execution of the being they have created - they call these beings The Dark breed.
What will happen when two people find out that they had accidentally made one dark breed of their own?
What will happen to the little dark breed?