If you kill the mother of a puppy, separate the puppy from its sibilings, kick it, abuse it, probably starve it, torture it, keep it locked up, let it escape and run away so you can run it down to kick it some more, make it live in constant fear of you.....
Then that puppy will grow up into a REALLY ****ed off dog, that will have been socialized to oathe and despise you and anything with your scent. But do you call the dog a stupid emo douchebag, when it lashes out and mauls it's abuser right in the ass-cheeks? No, you blame the owner who did this to the dog, and punish them for their crimes against the dog.
Then you work on rehabilitating the dog, then which Kat comes into play. You work with the dog little by little, get it to open up to you, and try to love it. Eventually, the dog will learn that not everybody wants to harm him, that somebody loves him.
But if you try anything ever again, that dog will still have one mother ****in' mean ass bite.
Sorry for the graphic explanation guys, but I wanted to get my point across.