The band - consisting of brothers Joe, Nick and Kevin Jonas - kicked off their 20th anniversary tour on Sunday at MetLife Stadium in their home state of New Jersey. But to make it more special, they surprised their fans with some special guests throughout the show, including Demi Lovato.

Camp Rock one and two were both huge successes for Disney Channel and made household names out of Nick, Joe and Kevin Jonas as the Jonas Brothers and of Demi Lovato. They all toured together as a group and then Demi Lovato revealed that after Camp Rock 2, her and Joe Jonas dated each other briefly but realised they were better as friends.

On Sunday, Demi Lovato joined the Jonas Brothers on stage in New Jersey for the opening night of the JONAS20 tour, dazzling in statement-making rhinestone-covered jeans. For the “Camp Rock” reunion, Lovato, 32, slipped into a pair of slouchy crystal-adorned Acne Studios jeans ($1,400).