Plenty of famous friends have joined Taylor Swift on stage throughout her 1989 tour, and during Sunday's show in Chicago, she sang a duet with country star Sam Hunt. Taylor and Sam performed his song "Take Your Time," and she later mentioned the moment in a cute Instagram snap. Posting a picture of the pair sitting on a bench on stage, Taylor wrote, "A huge thank you to @SamHuntMusic for surprising the crowd with 'Take Your Time'. Such a star." Keep reading for more pictures plus a video of Taylor and Sam's performance, then check out the sexiest pictures of Sam Hunt and an adorable throwback photo of the country star.