The twisted families that facebook has offered the opputunity for us to create. They often involve incestuous relationships between siblings, and parents. Older facebook users, such as grandparents sometimes need clarification.
"You have a baby with your sister, who is also your wife?!?!?!??!!"
"No, dude, thats my facebook family."
"Charlie, you're married to a man, and you have children?"
"No, Grandpa, thats my facebook family"