call them European Royalty
That bunch has it’s own definition of incest - calls it “good breeding”.
I did not think any state allowed first cousins to marry any longer but...
State Laws Regarding Marriages Between First Cousins:
Twenty-five states prohibit marriages between first cousins. Six states allow first cousin marriage under certain circumstances, and North Carolina allows first cousin marriage but prohibits double-cousin marriage. States generally recognize marriages of first cousins married in a state where such marriages are legal.
http://www.ncsl.org/default.aspx?tabid=4266