Which set of siblings co-starred as siblings in the 2001 film "Donnie Darko"?

Jake Gyllenhaal garnered an Independent Spirit Award nomination for Best Male Lead for playing the title character in the indie cult hit Donnie Darko (2001), in which he played a psychologically troubled teenager alongside his older sister, Maggie Gyllenhaal.

Donnie Darko is a 2001 science fiction film written and directed by Richard Kelly. It stars Jake Gyllenhaal, Jena Malone, Drew Barrymore, Mary McDonnell, Katharine Ross, Patrick Swayze, Noah Wyle, and Maggie Gyllenhaal. The film follows the adventures of the troubled title character as he seeks the meaning behind his Doomsday-related visions.

Filmed over the course of 28 days (coincidentally mirroring the time transpired in the movie), the film was almost released straight-to-video. Donnie Darko was screened at the Sundance Film Festival on January 19, 2001, before receiving a limited theatrical release on October 26, 2001 by Flower Films. Due to the film's advertising featuring a crashing plane and the September 11 attacks that transpired a month before, the film was scarcely advertised. In the end, Donnie Darko grossed just under $7.3 million worldwide on a budget of $4.5 million.