Good point !!!! And very frustrating !! I think it would depend on you and your knowledge of this child ! If this is something out of left field for this child I would def document and inform parents ! Beating with a stick is pretty serious !! Is it ok if it only happens every four months ? Unacceptable behaviour is unacceptable !! Doesn't matter the time line ! Childish behaviour and discipline needs to be different from malicious behaviour . It would come back to you and how you judge the situation .