A tough one for me as I was raised by a dad who would have literally kicked the shit out of the 5 year old if that had been done to me (and he never got charged by the police but they knocked on our door a lot when I was a kid). However I don't want to ever hit a child so what should I do? We were at the children's play area at our local park and my son had managed to climb up the steps to the top of the slide. This girl who I am guessing was about 5 climbed up the slide itself, meaning my son could not slide down it and then when she got to the top punched my son and shouted "move out the way" as he was obstructing the top entrance to the slide. I shouted at her "do not punch my son or you are going to be in a lot of trouble" half expecting a set of thuggish parents to come over and start a row but parents were nowhere to be seen. She said "he has the top of the slide and is not sharing" to which I replied "you climbed up the slide and blocked it so you are te selfish one and you have now punched a little baby making you a nasty girl" she shut up then. As I was not exactly set a good example growing up I have no idea of how to handle a situation like this. What re you supposed to do?