Should anyone else put their hands on my kids?

Not unless they are stopping them from hurting someone, stopping them from destroying something or saving their life, and all touching should be within reason for the situation. ie.) If your kid is beating up another kid it's ok for someone to restrain your kid to make him/her stop but it's not ok for them to beat on your kid to make him/her stop.

Also, in my opinion it is not ok for another person to punish your child physically without your explicit consent. ie.) you tell the babysitter it's ok to spank if the kid gets out of line.