Claim: Julianne Hough is the sister of Derek Hough.

Julianne Alexandra Hough -LRB- -LSB- hʌf -RSB- born July 20 , 1988 -RRB- is an American dancer , singer , and actress . She is a two-time professional champion of ABC 's Dancing with the Stars . She was nominated for a Creative Arts Primetime Emmy in 2007 for Outstanding Choreography in season five of the show . Her first leading acting role was in the 2011 film remake of Footloose . In September 2014 , Hough joined Dancing with the Stars as a permanent fourth judge . Along with her brother Derek Hough -LRB- who is a six-time winner of the dancing show -RRB- and Tessandra Chavez , she won the Primetime Emmy Award for Outstanding Choreography in 2015 . In 2016 , she played Sandy in the live Fox television production of Grease .