bcipam, I am sorry to hear of your family situation.

I'd suggest taking responsibility for your own reactions rather than trying to control or dictate other people's behavior. Tell your sister that you can't deal with people when they are upset, and ask if she could call you back later. Normally I would suggest reassuring her that you love her and value your relationship with her, but it sounds like that isn't true in your case. However you could tell her that emotional displays aren't your style, and reassure her that you will help your parents and brother in other ways.

If you don't want to participate in drama, don't participate in drama. When you start reacting and issuing directives about how people should behave, you are diving right in.

I admit that as an only child I am mystified by the extent to which siblings want to control each others' behavior (I exclude serious matters such as crime, substance abuse, child abuse, etc).

However, my father was one of eleven children, and the sort of thing you describe was what pretty much what they viewed as normal. As far as I could see, it did no good and caused a great deal of harm.

My comments are based on how I dealt with them and their endless squabbling and not on sibling relationships of my own. I can't claim any brilliant result but at least I maintained a sort of integrity, and it was fun to confuse them.

I wish you the best in dealing with your family's situation, which sounds challenging indeed. I also think Lisa's advice is very good.