I believe this can happen with any breed. My Parents had a retriever, (he was raised with us kids), and was a wonderful loving dog. When he got older, hegot agreesive about his territory and attacked someone when they didnt knock on my Parents door. Caused alot of damage to the kids arm, it was awful, and they could never trust him again. I was attacked as a kid, by a toy poodle, and have somescars on my face, but I still love poodles and retrivers....I feel you should "punish the deed, NOT the breed". My Noel is a Olde English Bulldogge, I understand they have pitbull in them. She is so sweet, but her jaws are strong, and huge!