When my oldest son was about 8 months old. His Grampa got a pit bull, that dog grew up with my son. I never had to worry about anyone coming up in the yard if that dog was out there with my son.
Pit Bull is used as a catch all phrase when it comes to a mixed breed dog. Any dog can snap and attack even the most gentle loving one. Even cats lately have been flipping out on their humans.
The dog isn't bad, it's bad training.