Patricia Rooney Mara (born April 1985) is an American film and television actress. Mara made her acting debut in 2005 and has gone on to star in films including A Nightmare on Elm Street, the remake of the 1984 horror film, and The Social Network. Mara portrayed Lisbeth Salander, the title character in the 2011 version of the film The Girl with the Dragon Tattoo.

She is great granddaughter of Tim Mara, founder of the New York Giants, and Art Rooney founder of the Pittsburgh Steelers.

http://en.wikipedia.org/wiki/Rooney_Mara