there isn't like a mean uncle figure to just smack him in the face once when this happens?
We try to talk through everything, we don't use punishments or rewards. But we do have boundaries, and he knows them. But hitting is one thing we are having a problem with. Hitting his brother when he does something to make him angry. We do talk about how you need to express anger with words, and we model that, we don't hit our children. We empathise with him about his frustration, and clarify what it is he needs.
I do not understand the theory behind not hitting children- daily and shit, for the hell of it, I understand why this is bad, but where in nature do you not see hurt and aggression as a means of instruction? If he doesn't learn now, he is going to be trying to talk out a problem with a knife-wielding subhuman with no critical thought, empathy, or language skills.
Obviously "modelling" non-aggression isn't working if he is hitting his brother when he is displeased. Sounds like he just needs to learn that violence is not some abstract and confusing mommy-speak concept, but rather, an actual stinging blow on his fat spoiled cheek.
"Ah, those endless forests, and their horror-haunted gloom! For what eternities have I wandered through them, a timid, hunted creature, starting at the least sound, frightened of my own shadow, keyed-up, ever alert and vigilant, ready on the instant to dash away in mad flight for my life. For I was the prey of all manner of fierce life that dwelt in the forest, and it was in ecstasies of fear that I fled before the hunting monsters."
Jack london, "Before Adam"