I went shopping at our local Sainsbury's. It's a big store with a large car park and I pulled into a space somewhere in the middle of the parking area. As I got my bags out of the car I noticed the window of the next vehicle was slightly open and then - to my horror - the reason was that there was a small child in a child seat in the back of the car!! Child must have been maybe 18 months or so, wide awake but quiet. Mother nowhere to be seen, so presumably in the store shopping. I waited by the car for a few minutes to see if the mother was going to reappear, but she didn't. While I stood wondering what to do, the child began to cry not surprisingly!! I should day I was just standing by my car, not staring in at the child or anything. So, I went into the store and reported it to the store security staff, who essentially said "not our problem" ...!! They refused to put out an announcement (I provided the car make and reg number), wouldn't send someone out to the car park or do anything about this at all.
AIBU to think 1) the mother behaved disgracefully(illegally??) to leave a small child like this and 2) the store security staff should have at least tried to alert the child's parent. I was in two minds about calling the police but really don't know what I should have done tbh .....