My son is and always has been very defiant - this is more than the normal 'testing' behaviour common in young children.
It can come completely out of the blue. For example, this morning he was perfectly cheerful and happy and wanted to play a CD. We asked him to turn the volume down as we were having breakfast and instead he turned it up. This continued and he refused to do what he was told. Instead he tried to throw his breakfast, pushed the table, flung a tea towel at me and called dp a big pig.
This is common behaviour and is often accompanied by violent tantrums where he hits bites and screams and kicks. I have to physically restrain him. He also throw things - ours and his, turns over tables and kicks the door if he is put into a room.
He has clear boundaries at home. The consequences of bad behaviour are that he is not allowed to watch TV. He is warned about this, but will say that he doesn't care and will continue with the bad behaviour. We often have to deal with a further tantrum when we carry through the threats.
We do encourage good behavoiur. We have a pasta jar and he saves up pieces of pasta towards a small treat of his choosing - gogos etc.
I have spoken at length to the school about this and he can be naughty at school too, but nothing like he is at home, so there's little they can do to help us.
He's not like this all of the time - I would say we have 75% good behaviour and 25% bad, but we're in the 25% bad zone at the moment.
His bad behaviour often coincides with a change in his life - ie start of new school term, new or disruptive children in his class, holidays etc.
I can talk to him about it and he says he doesn't know why he does it and that he can't help it. I've done role play to help him to work through how to deal with particular situations. This can help a bit, but his impulse to get angry is stronger than his ability to reason, so when push comes to shove he hits out.
Any advice welcomed.