Alden Ehrenreich and Tye Sheridan play American soldiers in Iraq only one of whom returns home.

Aniston plays the mother of Sheridan’s character, who becomes distraught after his fate is revealed.

Porto, during that film’s production.

Office Christmas Party LA Premiere

Credit: Jonathan Leibson/Getty Images

“For the whole shoot, they kept talking about this movie,” Aniston recalls.

and we both looked at each other and said, ‘Gladly.

Aniston has been producing more in recent years and finds the role to be especially gratifying.

The Yellow Birds - Still 1

Sundance Institute

“I mean, as actors, to be funny, you have to be able to be sad.

All of the emotions are in us,” Aniston says.

But that doesn’t mean she’ll be abandoning her funny movies.

“Look, here’s the truth: I love comedy.

It’s something that makes me happy, it brings me joy, it brings people joy.

We live in a pretty dark world as it is,” she says.

The Yellow Birdsis of the crying-all-day variety, but Aniston is fiercely proud of it.

“It’s like a beautiful portrait of a film,” she says.

“It’s hard, but it’s beautiful.”

The Yellow Birdspremieres at the Sundance Film Festival on Saturday, Jan. 21.