It's a question they have both received throughout their career:
Who is that song about?
Carly Simon has been grilled numerous times regarding her past relationships with Mick Jagger to Warren Beatty, while Taylor Swift continues to be asked about John Mayer... Nick Jonas... Jake Gyllenhaal and many others.
So it was only appropriate Saturday night at Gillette Stadium for Swift to bring Simon out and for the pair to duet on "You're So Vain." Watch the performance now:
Follow our link for plenty more Taylor Swift videos from her ongoing tour!