Sometimes you just have to take the bull by the horns and say "TOO BAD THIS IS THE WAY IT IS IF YOU DON'T LIKE IT TOUGH" but realize they may not talk to you ever again - and that could be a blessing and a curse. Example: my brother and I had it out (he and I never spoke again) then six months later he died. For six months I didn't have the yelling and screaming coming at me... but now did he know I loved him even though he would do that to me? I have to tell myself that he did - because he was sick.
a little more info would be helpful.
Do you have a question? We have been though all forms of sybling issues you can imagine. So ask away