Jacob Benjamin Gyllenhaal ( ,<ref><br />Gig Patta: Good, good. And, um, just to wrap things up, I know you've been asked, you know, hundreds of times—I mean, how do you really pronounce your last name?<br />Gyllenhaal: How do you think you pronounce my last name?<br />Gig Patta: I thought it was pronounced /ˈdʒɪlənhɔːl/.<br />Gyllenhaal: You got it! That's it.<br />Gig Patta: Is that really...?<br />Gyllenhaal: Yeah, there's no need for me even to say it. You got it perfectly.</ref> ; born December 19, 1980) is an American actor who has worked on screen and stage for over thirty years. Born into the Gyllenhaal family, he is the son of film director Stephen Gyllenhaal and screenwriter Naomi Foner, and the younger brother of actress Maggie Gyllenhaal. He began acting as a child, making his debut in City Slickers (1991), followed by roles in his father's films A Dangerous Woman (1993) and Homegrown (1998). His breakthrough roles were as Homer Hickam in the biopic October Sky (1999) and a troubled teenager in the thriller Donnie Darko (2001). Gyllenhaal expanded to big-budget films with a starring role in the 2004 disaster film The Day After Tomorrow. Wikipedia