Taylor Swift Singing With Selena Gomez

Hey there, I'm Karli Bulnes. Selena Gomez surprises an arena full of fans by singing with Taylor Swift, while boyfriend Justin Bieber does all he can to prove that paternity claim is false. It's all in PopSugar Rush. Just days after rapping from their front row seats at the American Music Awards, Selena Gomez and Taylor Swift took the stage Tuesday night at Madison Square Garden in New York to sing together for the very first time. The crowd at Taylor's concert went wild for the former Wizards of Waverly Place star, as the two friends belted out one of Selena's tunes, "Who Says." The duet was a great way to finish off Taylor's tour in time for Thanksgiving, and a reflective Ms. Swift tweeted to fans, "I have so much to be thankful for this year. I'm leaving New York, replaying this tour in my mind. I love you all so much." Meanwhile, Selena's love Justin Bieber performed on The Today Show this morning, and even got Matt Lauer to join in on the fan squealing. But all fun aside, Justin is taking the claim that he fathered a child very seriously, telling David Letterman that he did indeed take a paternity test and that he knew from the beginning that it was all untrue. "I could smell a weasel./A weasel? A weasel. I mean I think I could smell a weasel, too." You can watch Justin's full interview tonight on The Late Show With David Letterman on CBS.