I have a son that is 17 with aggressive behavior. I have seen that the aggression gets less frequent, (we went through daily episodes) but the aggression is more terrifying now, although the episodes seem to be about 1 or two a month now. (Full moon, isn't that odd?) But since he is so much bigger and stronger the violence is frightening.
I don't know if this will help you, but we found that the duration and the severity decrease if there is no audience. By this I mean if my girls and I leave, he calms down faster.
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