K.U.
I would strongly recommend looking into some kind of family counseling, as well as possibly individual counseling for him alone. A lot of it sounds pretty normal for the age he is and the situation he is in, but that does not make it acceptable. Counseling may help with any communication issues there may be between all of you. Taking some time to just to some fun things with him one-on-one might help since he seems to need more attention. My stepson could be much the same way and it's amazing to me to see how on his own he's a great kid to be around but when his older brother is there too, he turns into a jerk and has a horrible attitude about everything. There is a book called "How To Talk So Your Kid Will Listen and How To Listen So Your Kid Will Talk" which you may find helpful when you need to have a discussion with your son about his behavior, and how he can't be the center of attention all the time. But if you can get his dad on board with the counseling, maybe he will start to see how trying to "buy" his son's love and trying to be his friend instead of his parent is only making things worse. Dad needs to realize he is only rewarding his son for acting out and needs a serious wake-up call. Maybe he will take it better from a 3rd party "expert" than he will from you.