We were at a large party last night. Adults and kids were all there. The hosts had a couple of bouncy type things in the yard. Kids were playing on that while the adults hung out a tables in the backyard. There were a few teens who were near the bouncy stuff so we felt fine about our 9 yr. old son playing with his friends. When we decided to leave and find him, his lip was bleeding and his shirt was filthy. Turns out a slightly older kid started hit and kicked him to the ground. (Our son cut in line)We were furious but couldn’t talk to the parents because they already left the party. How do we deal with this situation now? Our son doesn’t want us to call but I feel like they should know what their son did!