maybe you yourself can just put this delima aside during the time of the family get together. be with your family and enjoy the "reunion" of all being together again .. the rift going on between you and your sister really doesnt "belong" in this occasion. you and your sister are both adults ... the dispute is between you and her & there is no need to involve other members of your family in it. dont ruin things by draging your drama into this. set your differences aside and enjoy the oppportunity of getting to spend this time together as a family.