Italiangreyhound - sorry, but she does come across as neurotic and over-possessive. She fostered because she was desperate to adopt if at all possible, not because she really wanted to be a foster parent; she was unhealthily obsessed with having another child, and I don't believe for a minute this was all for her son, it's just her excuse to justify an incredibly strong desire to have another child, which obviously did send signals to her son that he was not enough for her or quite what she wanted, given his discussion with the social worker on the Downs (not that this isn't an uncommon fear to be allayed by parents when they adopt, foster, or even have more children of their own); she comes across as extremely fragile and even before she let Kiri go off to see her grandparents, not mentally in a good place; and she's busy going on TV at every opportunity to throw blame around, which is rather nauseating, tbh.
As for the social worker, there is nothing to suggest her decisions with regard to this family were remotely affected by alcohol, so I am not getting why you think this makes her blameworthy with regard to Kiri's death. Leaving the dog hanging around in the car, though, I agree is a bit off, albeit nothing to do with her decisions on this case again, more just I feel sorry for the dog being left in the car all over the place, but the inconsistency of not going into the grandparents' house because of the dog is more likely her excuse because being a social worker, she would have had other things to deal with - in fact, I think she was late for a legal hearing. If she had gone into the house, it would have made bugger all difference anyway, as the son was not in there at the time. And the grandfather was a person she trusted and social services had trusted enough that they originally wanted him to care for Kiri, anyway. He had seen his granddaughter many times and was trusted. So no, I'm not going to blame a social worker for being responsible for someone's death because she has a dog and a hip flask!