Nah I think there's a middle ground. Absolutely think it's her fault, would love for her to be punished. Utterly shameless for her to try to pin it on the SW too.
That said, I only think it's "fault" in a direct sense, not a wider sense. Actually, to me, "fault" is a stupid word to use because it holds pearl-clutching, prayer-tutting Victorian notions of morality. I prefer a more practical and realistic perspective.
Like I said above, council house kids I've taught are mostly little angels growing up. But later, so many of them turn into mirror images of their parents who often aren't fit to be called human. As a teacher I can't fix their wider environment or even their shitty classroom environment.
The cute little boy in this story might well be copping flack on Mumsnet as a negligent deadbeat parent / disgrace of a human being if he had stayed alive and grown up.
Whereas I have taught so many delightful Charlottes and Georges who stay that way into their teens and young adulthood because they've had a positive and nurturing environment growing up.
Obviously exceptions always exist but in general, there's a reason why lifestyle and family dynamics repeat themselves generationally. Environment matters, end of story. Sorry but only an idiot would think otherwise.