Question for future parenting?

On my last few questions I asked if I should let my daughter go through with kicking my son in his testicles for his constant groping her while they rough-housed. Of the serious answers most supported the idea of letting her defend herself and said he deserved some punishment for his actions. So I went ahead and let her do it! He was in quiet a lot of pain but it really got it through to him that he can touch girls however he wants. Now if they start arguments or physical confrontations with each other again would it be okay to let her kick him there as a reaction instead of coming to me? Should I punish her if she defends herself in the moment with a kick to the groin?