well i'm pretty sure cousin mariage is fine but sibling is either
1. illegal
2. good luck finding a fucked up minister to do the ceremony.
i mean people are getting all worked up about people UNRELATED yet the same sex having sex (though i'm not sure how...nor do i really wanna know)
what american hero says is true, let people fuck who they want, as long as they dont televise fucking their mom to the public nobody will ever know.