family wreath
People that are inbred are said to have a Family Wreath, as there are no branches, only a circle of family.
Bubba went to the library to get a copy of his Family Wreath for his Dad/Uncle/Brother Travis.
Family Wreath
Instead of a Family Tree, this term refers to a family derived from a lot of incest.
Jed: Shit, you know they all marry their cousins!?Inbred sons of bitches ain’t got a Family Tree, they got a Family Wreath!