Celebrity Happy 25th Birthday, Elizabeth Olsen! See How Her Style Has Evolved By Josephine Cusumano Josephine Cusumano Josephine Cusumano is a writer, editor, and content specialist. She covers all things fashion, celebrities, and lifestyle. InStyle's editorial guidelines Published on February 16, 2014 @ 08:56AM Pin Share Tweet Email Photo: Bruce Glikas/FilmMagic, Mike Coppola/Getty Images Elizabeth Olsen may be Mary-Kate and Ashley's younger sister, but these days, she's definitely standing out all on her own. Today, Olsen celebrates her 25th birthday. From her short-lived cameo appearance in her sisters' 1994 film How the West Was Fun, to her breakout role in 2011's Martha Marcy May Marlene, which earned Olsen a Critics' Choice Award nomination, she has become one of Hollywood's biggest rising stars. Since then, Olsen has busied herself with a handful of films—including Silent House, Liberal Arts with Josh Radnor, last year's Kill Your Darlings, Oldboy, and this month's In Secret—and she's already gearing up for her first major blockbuster film, Avengers: Age of Ultron. She will staras Scarlet Witch opposite of Hollywood heavy hitters Robert Downey Jr., Chris Evans, Scarlett Johansson, and Chris Hemsworth. Not a bad way to kick off the new year! To celebrate Olsen's birthday, look through our gallery to see how her style has changed from a Campbell Hall School student to Hollywood A-lister. MORE:• See Elizabeth Olsen's Best Looks Ever• Olsen Stars In the Latest Miu Miu Campaign Ads• Olsen Screens Oldboy in New York City