The Sing-Off 'The Sing-Off' to return with a two-hour holiday special in December on NBC 11/07/2014 The Sing-Off will be returning with a holiday special in about a month. Read More RELATED NEWS Kirstin Maldonado: I love how Pentatonix inspires young singers'A Pentatonix Christmas Special' featuring Reba McEntire and Kelly Clarkson to air on NBCNick Lachey and Vanessa Lachey welcome baby No. 2 into their family TAGS: The Sing-Off James Sun Nick Lachey Patrick Stump Mark Burnett Shawn Stockman The Sing-Off
