From PEOPLE Magazine Click to enlarge
On a chilly day in March 2010, the passengers on the 8 a.m. Acela train from New York to Washington, D.C., did a double-take as two petite passengers took their seats. Among the rows of navy business suits and loafers, there sat Ashley Olsen wrapped in a cashmere sweater and her sister Mary-Kate in a chic black coat and a fedora. Both were rocking sky-high heels. "There was definitely a little buzz," recalls designer Nanette Lepore, who traveled with the duo as part of a lobbying effort to save New York City's beleaguered garment district. A few hours later, the actresses turned designers were engrossed in a deep discussion in the East Wing of the White House with Susan Sher, First Lady Michelle Obama's then chief of staff, about their cause. "They are not just using their name," says Lepore. "They are very invested. It's their passion."

That passion-along with a talent for impeccable tailoring and an instinct for what women want-was recognized on June 6 at the prestigious CFDA Fashion Awards in New York City, though nominees Mary-Kate and Ashley ultimately lost the new-talent award to designer Prabal Gurung. "They're among the few celebrities with a fashion brand who do it successfully," says Project Runway's Nina Garcia. "There's nobody pulling the strings there. It's those girls doing all the work."

It's a new chapter for the Olsens, who first hit the spotlight as 9-month-old cherubs on Full House and later became a constant fixture on the late-night club scene during their college years at NYU. "They were being normal kids. In college, you go crazy," says a fashion source. But in recent years, "they just really grew up," says the source. Since launching The Row, the twins-who will be 25 on June 13-have turned that label into a $12 million annual business and expanded their design empire (see box below). "Hopefully we offer something a little different and a little more exciting," Ashley told PEOPLE last year.

But aside from introducing a new line of handbags, the Olsens aren't trying to plan too far in advance. "We don't necessarily know what we're doing tomorrow," Mary-Kate has said. "If you'd asked us 10 years ago if we thought we'd be here, we probably [would have thought] it'd be a stretch."