This question has always been on my mind since Star Wars - The Empire Strikes Back.
When Leia kisses Luke and you know what Luke was think after that... how do you think he felt when he found out she was his sister (hopefully I didn't spoil the movie for anyone

). He probably though it was ok because at that time he had no idea she was his sister, she was just another deer grazing in the field to him.
I know many girls that I would never want to sleep with because of my relationship with them.... If Natalie Portman was a cousin and scored with her and never found out she was my cousin, how wrong is that? Of course am not talking about re-production here...
OK, that's enough out of me before I lose all credability on these boards
