Well, this is a musical act that probably won't go on tour any time soon: Prince William and Taylor Swift joined Jon Bon Jovi on stage at a charity event at Kensington Palace yesterday, where they helped him sing "Livin' on a Prayer," the Guardian reports. Swift acts predictably showboat-y as William acts predictably British. The performance was part of the Winter Whites Gala; upon her arrival, Swift told Us, "Oh my god, this is so incredibly exciting to be performing at Kensington Palace. It's all so Christmas-y. It's kind of surreal, right? I'm at a palace!" (More Prince William stories.)