What was the mother supposed to do, then? Say to the girl, no you can't do that, but you can sleep overnight in a sleeping bag in your own doorway, just to see what it's like!
Being slightly more serious, I'd be allowing her to do anything she wanted to do.
Her dad has just had a second operation for a brain tumour. He is having chemo at home, and is having fits. They are putting off having radiotherapy at the moment, to give as long a gap between the first and the next.
If telling the government off for allowing homeless people to sleep in doorways takes her mind off it for a few minutes, good.