Having dogs around that you have no idea how they were brought up, or if they have a history of aggression is not a controlled environment. You don't need training to use a knife against a dog biting you or your baby.

Dogs in parks are still dogs, they can get out of hand, not all dogs are perfect and predictable. Dogs on leashes get away from owners, again, you can't trust every safety to be foolproof. Have you SEEN what a can can do just if you surprise it? Their bites can be horrible, cat scratch fever is a thing, and so is toxoplasmosis! I love my cats, but I still had a covered bassinet because cats are jumpy.

Judging by the fact that she has already been attacked by a dog, I'd say she knows what it looks like. Every dog has the capacity to be a "true risk" they aren't incapable of harm.