The Ross Sisters Trio dancing to Solid Potato Salad

(via WTH & Boing Boing) I was blown away when I saw this years ago and was happy to come across it again! This featured vintage video showcases the crazy sibling contortionists, The Ross Sisters,¬†performing Solid Potato Salad to the 1940s movie Broadway Rhythm. ¬†What are the chances that all siblings have this gift?