Has anyone seen him? Since DS1 hit 3.5, he's turned from a considerate, gentle, caring, happy boy to an angry, grumpy, aggressive whinger. I'm not too sure how to handle it.

Last night he was mucking around brushing teeth so I sent him to bed with no story. On the way to his room he slammed the corridor door, then his bedroom door, then kicked it for good measure (I was right behind him so I saw it all). I told him as a consequence he wouldn't get any screens today. He got upset at that but went to sleep ok. This isn't out of the blue, we've talked about speaking nicely and respecting our property and I've warned him he needs to smarten up or he won't get to watch TV or do fun things like play on the iPad, so it didn't come out of nowhere.

Anyway, this morning he and DS2 are outside playing, DS2 comes running inside crying, I ask DS1 what happened, his answer was the DS2 destroyed the game he was playing (likely true) so he pushed him over. I told him he needed that's not how we behave, if DS2 is upsetting him to call out to me and I will help, then I told him to go inside and have some quiet thinking time, his response was "Dammit!" as he stomped off. I stopped him and said we don't say words like that, no TV tomorrow now either, at which he spewed forth pretty much every bad word he knows (poo bum stupid dammit ) so I said right no TV the day after, shall we continue? He stopped then but still flounced off to his room with great anger and slammed the door, again.

I don't know what to do! He's just so angry! Every response is physical - push, hit, throw something. Is this just a testosterone-fuelled thing? What sort of strategies should I be giving him to help deal with it?