7 year old touching family members' privates
My 7 year old son has started touching his siblings' privates as well as mine and my husband's privates when he gets upset about something. I suspect he feels powerless in those moments, and this the way he can feel some control (?), but I really don't know. Since the kids were very young, I have told them "privates are private" when it made sense in a discussion like at bath time, etc., and that isn't enough lately. There are times when he comes to me and I think he just wants a hug, and instead he will touch my behind or somewhere else. I asked him if someone touched him, but he says no, which I hope is true. I want to respond calmly and not be angry because it seems that there is something he needs to communicate and this is how he is doing so, but it is upsetting, and I am increasingly frustrated and dumbfounded. I try to practice gentle/respectful parenting, and don't know what to do at this point.
Thank you in advance!