WATCH: Taylor Swift and Carly Simon Sing “You’re So Vain” at Boston Concert

(YouTube)

Taylor Swift was joined onstage by the one and only Carly Simon at her Foxboro concert on Saturday night.

The singers performed a duet of Simon’s famous track, “You’re So Vain.”

VIDEO BELOW

Simon’s song is rumored to be about Warren Beatty, but we wonder whom Swift had in mind while belting out the tune.

Check out the video below!

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