Why is everyone immediately blaming the child's mother?

Re the kid who fell into the gorilla enclosure and they had to shot the gorilla to save the child’s life. I’ve read two memes that place the blame on the mother. One even labeled her as a “bitch.”

I’ve done some poking around, and at this point we don’t know anything more than the kid fell in. So why are we automatically blaming the mother?

It seems to me that men tend to lose track of their kids more than women do. I can’t count the times I’ve seen a father walking through a parking lot, or across the street, with a little one trailing behind and the father never even gives a glance back. From what I’ve seen, women are more likely to hold the child’s hand if possible, or at least keep them by their side.
My guess would be that the father, or some other male caregiver, was the one responsible.