Style Evolution: Ashley and Mary-Kate Olsen

When Full House debuted on September 22, 1987 the plan was for sassy Stephanie Tanner (Jodie Sweetin) to be the star. But all that changed when 9-month-old twins named Mary-Kate and Ashley Olsen showed up to play the youngest Tanner sister, Michelle (right, in Bob Saget's arms). Indeed, the tiny duo never played second fiddle, whether stealing the show for eight years on Full House or ruling the red carpet. Watch the girls grow from America's favorite tots into Hollywood's most fascinating fashionistas.

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Though they're actually fraternal twins, the pint-sized stars spent more than a decade dressed identically. Ashley (the older twin) and Mary-Kate wore floral frocks to a 1991 Full House press junket in Los Angeles.

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These cute-little-French-girl get-ups were picked for a fan meet-and-greet in 1993. One look at those hats and someone should have used the girls' most famous catchphrase to warn their stylist: "You're in big trouble, Mister!"

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Appearing at the Audrey Hepburn for Children Film Festival in 1997, it was clear that the twosome had already learned how to wield what would become their trademark accessory: oversized sunglasses.

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In 1992, the twins launched Dualstar Entertainment, to make Olsen-themed movies, TV shows and video-games. Looking like the mini-moguls they quickly became MK and Ash started started wearing adult clothing that had been specially cut down to fit, including these shiny suits, which they wore to the Spice World premiere in 1998.

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At 15, MK and Ash started getting more daring -- in a 'tween-star sense, that is. The girls flashed a bit of skin at the Jive release party for N'SYNC's Celebrity album in 2001. Wanna bet they both they both had a crush on Justin?

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You wouldn't guess by looking at their matching butterfly tops, but 2002 marked the girls' debut on the Forbes' most powerful celebrity list. By 2007 they were number 11, with an estimated net worth of $100 million. Talk about dressing for success.

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In 2002, the twins snagged a coveted invitation to the Vanity Fair Oscar Party -- though we doubt it was for best costume.

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The quickly maturing sisters were among the legions to earn a cameo in 2003's "Charlie's Angels: Full Throttle." Here, looking sweet and summer chic, they appeared at the blockbuster's premiere.

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Their all-grown-up movie -- 2003's "New York Minute" -- ended up in tatters. And it looks like the twins, shot on the "NYM" set, did likewise.

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