While actor's relationship with Reese Witherspoon recently ended according to a source, Gyllenhaal happily showed up without her at the premiere of Crazy Heart, which stars Maggie Gyllenhaal. Jake 28, stuck close by his big sis and their family for most of the night.
"He seemed very normal and relaxed, and very happy for his sister," said a fellow theatergoer. "Tonight was all about her."
In the film, Maggie plays a journalist and single mom who struggles through an off-and-on relationship with an alcoholic West Texas singer played by Jeff Bridges, whose bravura performance has already been garnering Oscar buzz.
According to a source, at the film's heartfelt finale, Jake, 28, wiped his eyes and nose and appeared to be fighting back tears.
Otherwise, the Brokeback Mountain star, who walked out of the theater arm and arm with his sister, seemed to have fun at the premiere, which was also attended by Sharon Stone, Gary Busey, and Eric Idle.
And while Witherspoon wasn't there, that did not keep the actress from supporting both the film and the Gyllenhaal family. On Monday, she attended a special screening of Crazy Heart at her talent agency CAA alongside Colin Farrell, who has a role in the film, and Orlando Bloom and Ed Harris.
"Reese is close to Maggie," a source tells PEOPLE. "She was beaming.”
With reporting by DAVID CAPLAN