In a kid who was only doing violence occasionally, I'd just act like they were about to do something nice. "You want to give sis a high five? Can I have one too??"
Yes, this is one way to "have expectations." My ds went threw a throwing stage when he was about 5. He'd usually throw something next to someone. He was always a kind of line walker, finding the line between acceptable and unacceptable and getting as close as possible... Not an anger thing at all. But if people reacted like he was going to throw the item AT them, he would. If they assumed he wouldn't, he didn't. I guess he figured if he was going to get the blame he might as well do the crime. It made some friendships work for us much better than others. The one good friend we made at that age had a spirited dd. The dd was just active and physical so my child being (nonaggressively) physical didn't make the mom tense. We also did better hanging out with people with older kids, especially boys. They weren't as tense. It's amazing how tense mothers of younger kids get and how they viewed my not so big kid as a dangerous big kid that they needed to protect their little ones from (this was with my ds at age 5 and he was always careful of the little kids so they weren't basing this on any incidents). I understand people wanting to protect their little ones but it was annoying to have them cast my rather sweet child as a bad guy.
Another thing that helped was positive redirection. I probably started doing it when ds was about 3. I started saying "watch for cars" instead "don't go in the street" or "remember to walk" instead of "don't run." That sort of language helped in two ways. It made ds feel like I was assuming the best rather than the worst and it didn't make him feel like doing the opposite the way saying "no" did.
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