Usher poses with his protege, Justin Bieber, at the "Christmas in Washington" holiday concert held at the National Building Museum in Washington, DC. The 15-year-old YouTube sensation was proud to sing Stevie Wonder's "Someday at Christmas" for President Obama and first lady Michelle Obama. Kevin Mazur/WireImage.com - December 13, 2009
Kevin Mazur
Mary J. Blige, Justin Bieber, and more get into the holiday spirit while performing for the Obamas in Washington DC.