CocoRosie

CocoRosie is an American musical group formed in 2003 by sisters Bianca "Coco" and Sierra "Rosie" Casady. The sisters were born and raised in the United States, but formed the band in Paris after meeting for the first time in years. Their music has been called "freak folk", and incorporates elements of pop, blues, opera, electronica, and hip hop.

source: Wikipedia