George Pimentel | WireImage
After performing a slew of hits off his current CD 'Under the Mistletoe,' Justin left the stage and brought back his fave little lady (sorry, Selena) to join him on the mic. Together, the adorable duo sang JB's hit, 'Baby.'
This isn't the first time little Jazzy (as her family and Bielibers call her) joined big bro Justin onstage. Back in February of this year, the tiny tot ran onto the set of a TV interview JB was conducting with 'eTalk.' The Biebs has also had his sister join him during concerts, like one recently in Winnipeg.
Watch Justin and Jazzy's adorable duet below. It must just give you a case of the "Awwwws!"
Watch Justin Bieber's 'Santa Claus Is Coming to Town' (Arthur Christmas Version)