Re: Marrying your cousin.
Some interesting facts about cousin marriages. First, it is common every where in the world and was a norm in the past. Second, United States is the only country that forbids cousin marriages, which has lot do with Catholic Church's campaign. Third, there is no scientific prove that suggests cousin marriages lead to birth defects in children.
Stats say the rest.....and I am sure that there is some scientific evidence...but even if there is no evidence would that justify you marrying your own sister.