My 17 year old daughter has a half sister on her fathers side that is 10 years older. While I respect the fact that she should be allowed a relationship with this girl (they didn't meet until a few years ago). Everytime she is around her I noticed an attitude change with me. The half sister has a tremendous amount of dislike for both her father and mother and my daughter is now starting to show this attitude with me as well as her father. Any ideas on how to combat this?