Syrum

Sometimes kids do those types of things for attention, to test you and to make sure you still love them. her reacting badly is reinforcing his belief that he is not lovable.

Do not ever withdraw love and affection from the children. Clearly they have been damaged by their mom and he is continuing to be damaged by your wife..

Have clear rules for all the children, and for you and your wife, including no yelling, no name calling etc. Everyone in the house sticks to the rules.

When he does something wrong all ways take him aside for time out. Talk to him about why what he is doing is wrong and how it makes other people FEEL. You need to teach him to have empathy for others. Something he's not getting from your wife.

If you love your son get counseling for him and the whole family.

It might be easy for your wife to point the finger at your son, but he is not the cause of the problems, something (his mom, and the situation with your wife or other things) are causing these problems, and as he's just a child, the adults need to own this problem.

if your wife has no older children her self she may never have faced these problems and realize that most families face these problems at some stage (even to a lesser degree), it is normal, but it's probably been hugely exasperated by the situation.

Remember also you can't control your son, you can only control how you react to him, and that can make the world of difference. Also your son probably feels like his world is out of control, and that is why he is doing those things.