These celebs know the reason for the season!

Justin Bieber, Mary J. Blige and Gavin DeGraw were among the stars to perform at the 13th Annual "A Home for the Holidays with Martina McBride" show. Katherine Heigl and her sister Meg Heigl-Beltran (who is adopted) introduced segments of the show, as did Denise Richards, who adopted baby Eloise earlier this year.

PHOTOS: Stars' good deeds

The annual event raises funds to help increase the number of adoptions for those children waiting in the United States foster care system. Wendy's International founder Dave Thomas, who was adopted, established the Dave Thomas Foundation for Adoption in 1992. Wendy's is a proud sponsor of this long-standing special that is presented in association with the Dave Thomas Foundation for Adoption and the Children's Action Network.

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For families interested in adopting a child from foster care, you can go to or call 1-800-ASK-DTFA.

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The 13th Annual A Home for the Holidays show airs Wednesday at 8 p.m. EST on CBS.

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