A*SHOLE COUSIN STAYING OVER AT HOME FOR A MONTH and Ruining My Little Sister's Life long sorry?

You, and your sister, are going to have to tough it out for the month. Do not tell your mother about the bad behavior of your cousin, she has enough on her mind without worrying about you. Your Dad should have a serious discussion with this cousin, he is abusive and mean. Maybe your Dad could bully him a bit.