As the topic says, what do other parents do in this situation?
Taking this morning as an example, we were at a park with a bunch of other Mums and toddlers when another boy pushed DS over. I watched him deliberately walk up and shove him with both hands fair and square right in the chest. I didn't see DS do anything to provoke him and I was watching him the whole time (we hadn't been there long). I think they were both walking towards the same piece of playground equipment so the other boy wanted to stop him. DS fell straight backwards and was pretty upset. I think he was just shocked more than anything that this kid would try to hurt him. He was weary of him for the rest of time we were there and wouldn't go anywhere near him. The mother of the other kid did try to get him to apologise etc for a bit. I reckon she was pretty embarrassed. I just sort of said 'It's okay, he'll be alright' but I'm not sure she heard me as DS was crying pretty loudly. I was just focused on trying to calm DS down and check he was okay. The other kid ran off happily and that was that.
Would you handle this any other way?