Honestly, a puppy chewing off 1 month old infant toes is a complete possibilty in my mind. When my daughter was 1 month old, her toes were the size of a pencil eraser. Some puppies are strong chewers at 6 weeks and little tiny toes are pretty soft.
I don't think this has anything to do with the dog being a pitbull. I think any breed would be capable of this. It's just a puppy doing what puppies do. The puppy didn't know what it was chewing.
As far as the parents not waking up to the crying who knows. They could have been on drugs, alcohol or at 1 month post-partum, extremely exhausted and slow to react.
I just feel very, very sorry for this baby. AND the puppy who will once again be a victim of irresponsible breeding practices and dog ownership. Who lets a 6 week old pup loose while they sleep :yikes: