My 9 year old boy was upset with his daddy for switching off his computer and not letting him playing computer games for too long. He told him he's very upset and quietly he hid his daddy's favorite books. His cousin hid his daddy's purse when similar thing happen. His other cousin hid his daddy's expensive watch and money when similar thing happen. Are these incidents part of child's development? What do you think we should do and say in order to make sure that they will be corrected or will not continue to use this method to get back on someone they are angry with. What would be the right method to release their anger? Will these behavior lead to "stealing" later on if not being properly handled? Please advise.