No but it's definately seems to be implied to me with all the focus on it being the parent's fault, or that the parent should be watching better- and yes, while that is 100% true, the fact of the matter is that the end result will still be injury to the child.
More than one adult can be at fault in a situation, but the adult who is responsible for the more dangerous creature or object is the one that, in general, needs to take greater precautions.
I should be able to drive my car at a normal speed on the road, but I am still not supposed to hit pedestrians if at ALL possible, even if they jay-walk. I am responsible for making sure my brakes are in good working order, that I am driving the speed limit (or slower, depending on conditions) and that I am on the lookout for pedestrians- even the ones that aren't where they should be. As the driver of a heavy vehicle that is my job. I can't just shrug and say "well, they shouldn't have been walking there, so I didn't bother beeping my horn to warn them or slowing down".
As a pet owner, your job is to keep the public reasonably safe from your pet, even the stupid or young members of the public.
I just don't understand why children must be 100% perfect from birth and parents never make a mistake, but a dangerous animal and a semi-reactive owner gets a pass for "just being an animal". I hear the excuse, what if this was the first time the dog acted up. Well, where is the "what if this was the first time the Mother was distracted, and the first time her child tried to wander around because normally she sticks right beside mum" excuse. You said in the OP she was around 4- for many kids that is the first time they are not in a stroller- maybe the mother wasn't used to her not being strapped down. Maybe that was her aunt, not her mother- her childless aunt who isn't totally used to small children and took the kid in an emergency for mum and brought the kid on an errand. Why do animals and pet owners get what ifs and excuses and not parents and kids?
Why is it impossible to use words the way they were intended- a "Lady, get the kid away from Kujo" shouldn't be impossible to manage....
Animals and humans have co-existed for years. However, we used to treat them as purely property, routinely putting down the aggressive ones, so I'm not sure you want to bring up that argument.
I also don't see why the child's actions are being misquoted. "Inching" is not the same as "lunging" in any dictionary I own.