Carly Simon joined Taylor Swift on stage at the Gillette Stadium on July 27 in Foxborough, Mass., to perform Simon's iconic 1972 single, "You're So Vain." The pair sang and danced around stage, reaching out to fans and embracing one another throughout the duet.
Simon came out carrying an apricot-colored scarf -- a reference to the song's lyrics -- before she and Swift broke into the song's first verse. By the chorus, fans were singing along too.
In a pre-concert interview with MTV, Simon admitted to sharing with Swift the long-kept secret of who inspired the classic song. Though Simon has never confirmed the subject of the song, there has been much speculation on the subject, including the rumor that it's about Rolling Stones frontman Mick Jagger, who sings the song's back-up vocals.
While we may never learn who "You're So Vain" is really about, we can certainly bask in the knowledge that T-Swift is keeping Simon's secret safe and sound.
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