"Ibarra said the dog was a high-dollar male that belonged to his friend, which he was keeping in his yard to breed to his female."High dollar male? You can see the dog's picture here.
For one, that isn't an American Pit Bull Terrier. His ancestors may have been, but he is not. He is a mixed breed dog who looks a lot like an American Bulldog mix. I have nothing against dogs who look like this dog, but very few actually qualify as American Pit Bull Terriers.
For two, I think the quote answers the question.
Allowing your children to play around an unknown dog is not smart. The dogs were kept outdoors, mostly. Add to the fact the dog may have been more hyped because of an in-estrus female around, and you have a recipe for disaster.
These are exactly the type of people who should not be breeding dogs.