President Barack Obama©, first lady Michelle Obama and daughters Malia and Sasha are joined by entertainers (L-R) Conan O’Brien, Jennifer Hudson, Victoria Justice and Justin Bieber for a final song at the conclusion of the performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

President Barack Obama (Center L), first lady Michelle Obama (L) and daughters Sasha (2nd L) and Malia (3rd L) are joined by entertainers Jennifer Hudson (Center R), Victoria Justice (2nd R) and Justin Bieber® for a final song at the conclusion of the performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. (Photo by Mike Theiler-Pool/Getty Images)

First lady Michelle Obama, Malia, Sasha and President Barack Obama join in for a final song at the conclusion of the performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

The Band Perry, Conan O’Brien, Michelle Obama and daughters Malia and Sasha; President Obama, Jennifer Hudson, Victoria Justice and Justin Bieber join together for a final song at the conclusion of the performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. (Photo by Mike Theiler-Pool/Getty Images)

U.S. President Barack Obama, first lady Michelle Obama (2nd L) and daughters Malia® and Sasha pose for a group photo with children dressed as elves prior to attending performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

President Barack Obama (Front Row Center), first lady Michelle Obama and daughters Malia and Sasha join the audience in the playing of the national anthem prior to watching performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

President Barack Obama, first lady Michelle Obama (2nd L) and daughters Malia® and Sasha greet children dressed as elves prior to attending performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

President Barack Obama, first lady Michelle Obama (2nd L) and daughters Malia® and Sasha greet children dressed as elves prior to attending performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

President Obama, first lady Michelle Obama (2nd L) and daughters Malia® and Sasha greet children dressed as elves prior to attending performances at the annual ‘Christmas in Washington’ gala on December 11, 2011 in Washington, DC. It’s the 30th anniversary of the ‘Christmas in Washington’ gala. (Photo by Mike Theiler-Pool/Getty Images)

From left, first lady Michelle Obama, Sasha Obama, Malia Obama, and President Barack Obama, sing “Hark! The Herald Angels Sing” with performers Jennifer Hudson, Victoria Justice, and Justin Bieber, at the annual Christmas in Washington taping at the National Building Museum in Washington, Sunday, Dec. 11, 2011. (AP Photo/Jacquelyn Martin)