[Politically Correct]

From the story (notoriously unreliable reportage) the grandmother (not the owner) was moving the dog (why is not stated) from the room that the owner had locked the dog in.
Dog breaks free and kills child.

The only one negligent is the grandmother (not the dog's owner) in her estimation of being able to control the dog (she was wrong).

I'm not sure that I'd be interested in claiming negligent homicide and exposing the grandmother to legal peril.

[familyop]

The dog’s owners are the mother and father of the child. They’re keeping the other pit bulls that they own.

After the her baby was mauled to death, the mother, “not ready to blame the breed entirely,” said, “I still don’t feel any type of way about a pit bull” (cited source below).

Pit bull fatally mauls 9-month-old in bouncy chair
http://www.freerepublic.com/focus/f-news/3659705/posts
New York Post ^ | May 31, 2018 | By Joshua Rhett Miller
https://nypost.com/2018/05/31/pit-bull-fatally-mauls-9-month-old-in-bouncy-chair/

[Hugin]

Pitbulls should be banned. Short of that, those people who insist on owning them should be criminally liable for anything they do, period. I don’t care if the owner wasn’t there, it’s his responsibility to see that it was controlled. If he left it in the care of a woman who couldn’t control the canine monster it’s on him.

[TexasGator]

Son keeps three pit bulls INSIDE his grandmothers house!!!!!!!!!!!!!

Mother drops baby off for Grandmother to babysit INSIDE the house with three pit pulls!!!!!

WTH would anyone leave their mother home alone with three pit bulls!!!!!!!!

[trebb]

Why not get to the meat of it - they had a dangerous animal in the house with a child - even though most adults would not be able to control the animal if it decided to go for the kill when they happened to be trying to handle it.....