that first dog looks more like a small Scott American bulldog bitch...not a pit.
btw...any dog will bear teeth and all lippy dogs slobber
Pits are too often (way) in the wrong hands...I know plenty that are fine but they are endemic in black thug and w-word community...hence the problem....
that said I would not leave any guard or fighting style dog alone with a child...even with Lassie you never know and then it could be too late
former owner of Alsatians, Rotts, Giant Schnauzers and Dobes...and currently looking for a decent Scott-Johnson hybrid male..with juevos still attached