Kellie Pickler may be part of the NBC special called 'A Michael Buble Christmas,' set to air on Dec. 6. The singer tweeted that she was in New York yesterday, and a celebrity makeup artist says Pickler was on stage performing a duet with Buble.

"Back stage with Michael Bublé and Kelly Pickler! They're singing the cutest duet together for Michael's Christmas show!," Belinda Moss tweeted on Thursday. It seems likely that the two singers were just rehearsing as a television ticket broker reports the real taping for the NBC special occurred on Friday, Nov. 4 in Brooklyn.

The special will promote Buble's recent album of holiday standards. The 'Christmas' album was released last month and it features a duet of 'White Christmas' with Shania Twain amongst the 15 songs. NBC's website confirms that 'A Michael Buble Christmas' special is scheduled for Dec. 6 at 8PM EST, but offers no further details on any additional guest artists or celebrities.