Flaunting that signature rock-n-roll style, tatted-up bombshell rebel Kelly Osbourne is a certified fashion diva of the highest degree. Not just the daughter of Black Sabbath frontman Ozzy, she’s matured into a superstar herself, with a wide range of talents as an actress, musician, designer, host, dancer, and writer. Lately, she’s been able to add the label of fitness guru, as she’s 70 pounds lighter, and fitter than ever! But how did she achieve—and maintain!—such an extreme change? Here’s a look at the stunning transformation of Kelly Osbourne.