I camp at festivals several times a year. The sites are large and I'm often quite close to people I don't know. So you hear stuff, in particular, parents shouting at the kids. After a few days, a pattern starts to emerge - Little Billy is always being shouted at. He's obviously a persistently naughty boy, or is he? Sometimes it sounds more like the parents are dumping their frustrations with life on the kid and there's nothing the child can do to stop it.
As I don't have children, I find it difficult to judge what's going on - not that it's any of my business, or is it? Should I quietly take the registration number of the car and pass it to the NSPCC?
Sometimes it is my business. I was once camped next to a mother who seemed to berate her daughter loudly from morn till night. It was a bloody nuisance so eventually I waited for mum to pause for breath and let out a loud "Ewwwwwwwww!"
Worked a treat! Didn't hear a peep out of her for the rest of the festival.