True personal story:
When my oldest daughter was about 8 months old, she got over-stimulated and grabbed an adult relative hard enough to cause pain. We pulled her off, apologized, went into another room and helped her calm down. About 20 minutes later, I apologized for my daughter's behavior again to my relative. Her response surprised me. She said:
"Are you going to let her get away with that? Shouldn't you give her a little swat on the butt?"