Justin Bieber has lined up Will Smith‘s talented son, Jaden, to join him onstage at Madison Square Garden on Aug. 31. The pop sensation invited Jaden to perform after the young “Karate Kid” star joined him in his video for “Never Say Never,” one of the hit movie’s theme songs. An MSG source told us, “Special security arrangements are being made for Jaden, who will appear onstage, and his family, including Will, to be in the audience for the concert.” Other guests listed for the show include Sean Kingston and Jessica Jarrell. A rep for Bieber didn’t get back to us.