Marrying your cousin
Although some view it with a negative stigma, the fact is you can marry your cousin in every state in the United States. The only issue is which cousin. At least 34 states go so far as to allow you to marry your first cousin, which is your aunt/uncle’s kid.
That being said, some states in which marriage between first cousins is permitted only permit it under certain circumstances (as in Arizona, where the couple must be over 65 years of age or in West Virginia, where only adopted first cousins are allowed to wed).