What do you think of PDA?

Yeah, I get uncomfortable as well. I never know where to look when I'm around people like that. I don't want to look at them, but their obvious displays of are kind of hard to ignore. I don't mind hugging, holding hands, or giving quick pecks, but anything more is very uncomfortable. Tell your sister how you feel about her behavior. Chances are she did not realize it bothered anyone. I'm sure she'll tone it down next time.