CocoRosie is a duo from America that was formed by Sierra Casady (Rosie) and Bianca Casady (Coco) in 2003. Sierra and Bianca Casady are American half-Cherokee sisters. Sierra, the older of the two, was born in Iowa, and Bianca was born in Hawaii. Their mother nicknamed them Rosie and Coco, respectively, from which their musical act takes its name. Stylistically they may be assigned to the indie rock, psych folk, folk-tronic genres, and are sometimes associated with the new weird america movement.