Div, have you tried focusing on good behaviour and using positive reinforcement when he does something good/kind/nice? It is hard when they can get soooo worked up and then become defiant - it really puts us at a loss as to how to handle it effectively. Do you have a reward system in place for him so when he does something *good* he gets a sticker and that can build up so when he gets x amount he gets a surprise/treat?

Naturally I assume that his father isn't like that *all* the time, so is it just being around him that triggers this behaviour in Alex or is it worse when he has seen his father have outbursts? My brother was a bit like that when we were back home after seeing our dad too - not because he was violent etc, but just from the emotional strain of having to leave his dad kwim?

I really hope you can make headway on this Div, because I'm sure he is otherwise a delightful little boy and it would be a shame for this to impact on him any longer than it already has.