Kelly McCreary is an American actress, best known for her role as Dr. Maggie Pierce, Meredith Grey's half-sister, in the ABC drama series, Grey's Anatomy.

She graduated from Barnard College of Columbia University in New York City in 2003. She began acting in college, appearing in numerous plays and commercials, before making her television debut on the PBS series Cyberchase.

In 2008, McCreary made her professional acting debut in the Broadway musical Passing Strange. In 2010 she landed a starring role in Perfect Harmony, a musical comedy about the search for truth, love, and high school a cappella championship glory, which played Off-Broadway in New York City. During her early career, McCreary also had a recurring role in the USA Network series, White Collar.

She made her movie debut with a small role in the 2011 drama film, Being Flynn, starring Robert De Niro and Julianne Moore. In 2012, she was cast in her first major role of her career, on The CW medical comedy-drama series, Emily Owens, M.D., opposite Mamie Gummer and Aja Naomi King, playing the role of Tyra Dupre, a first-year surgical intern who is a lesbian. However, the series was cancelled after one season.

In 2014, after guest starring in Shonda Rhimes' political drama Scandal, McCreary was cast on the ABC drama series, Grey's Anatomy in the role of Margaret Pierce, Meredith Grey's half-sister. McCreary had been recurring since the season 10 finale. However, after recurring on the first four episodes of season 11, she was promoted to series regular status on October 23, 2014.

In 2018, McCreary booked one of the lead roles in the Netflix animated series Harvey Street Kids, where she voices the character Dot. That year she also starred as Shanita in the Geffen Playhouse production of Skeleton Crew.

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