Question: 
How do you talk to a child, in this case my 6-year-old nephew, about how it is no OK for an adult to hurt you?

I've seen his mom be rough with him out of frustration and anger, and though I'm not in a position to confront her, I want him to know he can tell me if she really hurts him.

And, I just saw a video of a teacher who roughed up a 6yo in a hallway at school. I want him to know he can tell me anything, and that it is NOT OK for an adult, even his mom or teacher to hurt him, but at the same time not scare him?

Helping children understand that there are behaviors that adults do which are wrong is an important yet tricky thing to do. Parents want their children to respect adults but at the same time recognize when an adult is crossing a line and harming them. I have found that the best way to do this is to first identify any harmful behavior that would make the child uncomfortable. For instance, I would say something like this to a child, “Tommy, there are many things that kids and adults do which can hurt children- either by making them feel sad, disappointed or very upset. As a grown-up, I’ve known children who have had their feelings hurt by a classmate saying something mean to them at school but I’ve also known teachers who have said mean things to kids at school.”

After you say something like this, watch the child’s face closely to see if he resonates with what you are saying. You could continue with, “Often grown-ups go through times when they lose their tempers and hit kids or say hurtful things to them. Sometimes even parents do this- they don’t mean to, but they make mistakes like this. Has this ever happened to you?”

The best way to help a child open up to you is by keeping him from being defensive about his mother or father. If you come across as critical of either parent, the child won’t say anything because he feels it is his duty to defend his parent. If you identify things which hurt his feelings (something his mother might have said or done) and you present it in a way which makes him feel that you understand his mother and don’t want to demean her, he’ll talk to you.

Once he tells you what is going on, it is important for you to simply listen. Then, ask pointed questions about how he felt when that something happened. Talk about him, not his mother and you’ll stay on safe territory as far as he’s concerned.

If you find that his mother is abusive, then you need to intervene. Try to talk to her but don’t tell her that your nephew has been talking- this will come back to him and he’ll stop. Or, you could try talking to her close friend, husband, etc- someone who can get through to her. If you do talk to her, tell her that you are concerned because she appears stressed and that you want to help  her with that stress. Beginning with a conversation about her health, rather than her son’s will keep her open to what you have to say.