My DS is 5 and seems to get very frustrated at most things, usually if he is told he can't do something like play on the Nintendo DS or watch TV which we limit to one hour a day as a reward. He doesn't like playing with any toys as seems to find them boring and is happy to play with his younger brother for a while but they just end up fighting and my youngest will always get hurt! His constand answering back and being rude and lashing out is driving us to madness! Is this normal? Any ideas to calm him down?