Daddy Roulette
A bunch of guys all shoot their wad into a funnel attached to a girl's privates, then wait nine months for the baby to come out and see who the real dad is.
My dad got stuck with the dad role because he was the only one who shot his wad into the funnel.
My uncle got stuck with the dad role because he was the only one who didn't forget to put on a condom.
My cousin got stuck with the dad role because he was the only one who showed up to the hospital.