Britney Spears appeared on 'The Ellen DeGeneres Show' delivering 'Silent Night' with the TV show's host .
Britney Spears performed "Silent Night" with Ellen DeGeneres during her visit on "The Ellen DeGeneres Show". They first tried to croon "The Christmas Song (Chesnuts Roasting on an Open Fire)" but later decided to sing "Silent Night" instead.
Beside entertaining fans with Britney's live appearance, Ellen also managed to poke fun at the "Circus" hitmaker. "I had to keep teaching her about harmony," the stand-up comedian cracked when referring to their duet.
Previously, Britney Spears' father reportedly ordered all the dancers, who were picked up from an audition she held in Hollywood's International Dance Studio, to pass a drugs test before going on the road with her. "They all had to be drug tested and, if they didn't pass, they were fired," an insider told E! News. "I think they only do it for her because she is under strict watch. I think they just want good influences around her."
Britney Spears' "Silent Night" performance with Ellen DeGeneres: