@Brian2036 Any dog has the potential to do something they've never done before if they feel threatened.
My dog is large, looks intimidating (in the husky family and wolfish-looking), and has a big bark. She's also an alpha female, and while she's old now and has calmed down, she used to attack some female dogs if they got too close to her territory, i.e. our house, or me. She'd jump them, get them on their backs, and stand over them, snarling with teeth bared, and not let them get up. You expected to see blood and fur flying, but it was just a big show of dominance- she never actually bit them, nor has she ever bitten anyone or any other animal.
But one day I was standing out on the road chatting with some neighbors and their 5 year old was sitting on the ground near the dog. I wasn't paying any attention, as my dog has always been gentle with people. But he had been touching her near her tail, rather than her head, which is an area she's always been nervous about even me fussing around with, and she had turned around and snapped at him as a warning, which really scared him, with good reason.
Had she been a pitbull, that warning snap might very well have been a "clamp jaws on arm and don't let go", instead.