I did the same thing with a sheltie we had when our daughter became a toddler. She reached over a gate at the stairs to pet the dog who was on the other side and the dog snapped at her hand. I had to get rid of the dog as I knew I could no longer trust her around my toddler.
That is bizarre for a Sheltie. Of course, there is always the chance of an aberrant personality problem in any breed. I had a friend who bred and showed Shelties. When I visited her for the first time her 13 full grown dogs came out to greet me. They were intact males and females and I never saw one growl at another or me while I was there.As a stranger I was inundated with kisses, although a few were more aloof than others they too came around after a day.Three slept in bed with me. Beautiful breed.
I had two and they both loved babies. In fact my first thought he was a kid. He wanted to get on the school bus and actually trick-or-treated door to door with the kids. The whole neighborhood knew and loved him. He used to lay on the sofa with his head across the legs of our babies and they learned to walk by getting handfuls of long hair and walking behind him. Never growled or showed teeth to a human in his life.
There can always be a ‘bad’ dog in a breed.My aunt had a bi-polar cocker spaniel. As he got older he would get a crazy look in his eyes and snap at you if you petted him too long.
The trouble with pit bulls is there are so many BYB’s breeding fighting dogs that almost every pit bull alive has a violent ancestor still alive. It’s in the bloodline and I would no more trust a pit bull completely than I would a schizophrenic psychopath who is temporarily calm. And I like dogs more than most people.
I have another brother, who has a dog, a wife, and a child. The dog bit the kid when she was a toddler, but the wife/mother loved the dog more than her young daughter, she didn’t tell my brother, for fear he would give the dog away... They are a heck of a couple ;(