SHARON OSBOURNE: You Can't Fire Jack, I Quit!

Sharon Osbourne has turned all Mama Bear and walked out on NBC's America's Got Talent -- after the network fired her son Jack from one of its other shows. The producers of Stars Earn Stripes gave Jack a pink slip two days before filming started, and Sharon insists the axing was all about his multiple sclerosis diagnosis. She tells the New York Post, "It's discrimination and it was badly handled. I just can't be fake -- it's time to move on. They can't make me [return]. All they can do is stop me from being a judge on another network for five years."

An NBC rep told the Post, "We regret any misunderstanding and wish Jack well."