Sharon Osbourne broke down in tears on TV over her daughter Kelly Osbourne after she stunned judges with her fancy footwork on Dancing With The Stars.

The America's Got Talent judge watched proudly from the audience with her rocker husband Ozzy Osbourne as their reality TV star-turned-presenter daughter took to the floor in front of a packed audience.

The 24 year old performed a Viennese Waltz for her debut dance of the series, and blew her family and fans away with a step-perfect routine. And the show's three judges couldn't believe the transformation in Osbourne - who recently admitted she was forced to take the part of Mama Morton in a West End production of Chicago because she couldn't dance the lead role of Roxy.

Judge Bruno Tonioli exclaimed, "Kelly I cannot believe my eyes. The wild-child, rock-princess, transformed into a vision of grace, elegance in a world of impeccable style!"

The comments caused the star's rock matriarch mother to burst into tears, as the audience jumped to a standing ovation. Osbourne couldn't help blubbering herself, hugging her joyful parents, before saying, "I'm crying. That was the most fun I've ever had in my life. I can't believe I'm crying!"

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