Charles Sykes, AP
Fresh off taking his DNA test to settle the Mariah Yeater baby mama drama, Bieber was in the front row to cheer on his girlfriend Selena when she hit the stage to duet with her bestie, Taylor. Bieber himself was a surprise guest at an earlier Speak Now show, but it was his lady's who joined Taylor in the spotlight this time around.
Gomez, 19, and Swift, 21, sang together for the first time with a live collab on Selena's hit 'Who Says,' to the delight of the screaming audience. And the surprises didn't end there. After telling the crowd that she was named after Rock & Roll Hall of Fame singer-songwriter James Taylor, the man himself joined Swift on stage to perform his 'Fire and Rain' and her 'Fifteen' together!
Larry Busacca, Getty Images
Watch Taylor Swift and Selena Gomez Perform on the Speak Now Tour
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