The Year's Most Important TV Event

The holidays are all about giving back and CBS is teaming up with some of Hollywood’s biggest stars to do just that!

The 13th Annual A Home for the Holidays with Martina McBride airs December 21 and features the country superstar performing alongside Justin Bieber, Mary J. Blige, Gavin DeGraw, OneRepublic and Christina Perri as they share inspirational stories about adoption from foster care.

Stories of families who've adopted will also be introduced by Katherine Heigl (who adopted a child), her adopted sister Meg Heigl-Beltran and Denise Richards, who recently adopted a new baby girl.

With over a half million children currently in foster care in the United States, this hugely successful special aims to give these children voices by painting an intimate portrait of youth who need permanent loving homes.

The 13th Annual A Home For The Holidays with Martina McBride, presented by The Dave Thomas Foundation for Adoption and Children's Action Network, airs December 21 at 8 p.m. on CBS.