We were at a splash playground yesterday(a closed place, sort of a small water park, commercial place), where there's obviously a lot of water and exciting kids. Most of the kids were young, including toddlers, pre schoolers, and elementary school aged kids, etc and parents. Some kids were running (most were not). Then a 5 year old boy and an 11 year old girl bumped to each other and the boy fell down on his back and bumped the back of his head to the hard floor (concrete). He cried. His parents came to check on him and calmed him down. The girl went away without saying anything and her parents didn't show up either (the girl looked a lot bigger and older than a typical 11 year old). But then about half an hour later, the boy and the same girl obviously bumped together again. This time, the boy fell on his face and hurt his forehead, and mouth (lips and tongue, etc). The parents got upset and started talking to the park staff, to ask for first aid and talk about the event. Then the girl's parents came up and said she's the mom and asked the boy's parents to talk to her, not the staff. Then she said her daughter was sorry (in a polite, yet not a very apologetic tone) and she was only an 11 year old kid, etc. The boy's parents then went on checking the boy and decided they wanted the girl's parents' contact information. The girl's parents refused to give it and tried to leave the park. Then the boy's parents called the police.
If you were the boy's parents, what would you do?