In 2009 , American singer Christina Aguilera approached Sia about writing ballads for Aguilera 's then-upcoming sixth studio album . The final product , '' Bionic '' , includes three songs co-written by Sia . Later in 2010 , Sia also co-wrote " Bound to You " for the soundtrack of the American film '' Burlesque '' , which starred Aguilera and American singer Cher . The song was nominated for Best Original Song at the 68th Golden Globe Awards . In May 2011 , Sia appeared on the inaugural season of the U.S. version of '' The Voice '' as an adviser for Aguilera , who served as a vocal coach and judge
68th Golden Globe Awards
68th Golden Globe Awards
Sia (musician)