LOS ANGELES, Feb 19 (Reuters) - The teenage son of late pop star Michael Jackson has signed up to be a correspondent for the "Entertainment Tonight" television show, following in the footsteps of his show business family. Prince Jackson, 16, was to debut on "Entertainment Tonight" on Tuesday, interviewing actors James Franco, Zach Braff and director Sam Raimi as they promote their upcoming film "Oz the Great and Powerful," the program said.