Rant- disown my sister

Just so tired of my older sister. She's 30 and still acts 15. My family had a get together for the fireworks yesterday like we do every year and last night ended with her calling my 3 yo boy a bastard child -which he is not) she assaulted my husband , punching him in the head while holding her 16 month old son, then went on to hit me! This is not the first time she's done this, and her boy friend was involved as well . just tired of them . my children witnessed all this garbage and they were so scared!! My kids deserve better!