Transformation

Mary-Kate and Ashley Olsen may be fraternal twins, but there's little alike about their favorite beauty looks. As Mary-Kate has said, the duo have been wearing makeup "since we were nine months old," and their tastes have run the gamut from cheery purple shadows to smoky kohl liner. These days, Ashley favors "old-school beauty" while Mary-Kate was loves to experiment ("I woke up one morning and was like, I want white-trash hair"). When not pursuing acting roles (Mary-Kate stars in the upcoming The Wackness), the sisters keep busy with their Dualstar empire, which includes their new clothing lines, The Row and Elizabeth and James.

1991: The 4-year-olds share the role of Michelle Tanner on Full House.