(ROUGH CUT ONLY - NO REPORTER NARRATION) The Obamas attended an annual holiday concert that benefits the National Childrens Medical Center on Sunday (December 9). This year's "Christmas in Washington" concert included some controversy and something non-traditional: a performance by South Korean "Gangnam Style" rapper Psy. Psy engaged in anti-American protests eight years ago. He issued an apology Friday (December 7) for the "inflammatory and inappropriate language" he said he used in a rap as "part of a deeply emotional reaction to the war in Iraq and the killing of two Korean schoolgirls". But the controversy didn't affect Obama's attendance. U.S. presidents traditionally attends this charity event, which is in it's 31st year. Hosted by comedian Conan O'Brien, other performers included Diana Ross, Demi Lovato, Scotty McCreery, Chris Mann of "The Voice" fame and "Smash" star Megan Hilty. The concert is scheduled to air on December 21 on the American Cable television station TNT.