What's their relationship like? Are you married to/do you see yourself marrying someone like one of your parents?
I think my mom is an ISFJ and my dad is an ISTP. Their marriage= EPIC FAIL. I don't want my future spouse to be at all like either of my parents. They never communicated their intentions properly to each other and my dad never expressed his feelings. Their F and T functions really clashed, but if they had made an effort they probably could have coped with it better. After witnessing the slow death of their relationship, I'm convinced that as an F, it is necessary for me to marry an F who is sensitive and in tune with his emotions and easily expresses them.