Sarah Silverman spoke to ET about her battles with depression, and while talking about her new film I Smile Back also opened up about her mother's death last month. 

In the dramatic indie film, which premiered at Sundance and will screen at the Toronto International Film Festival this weekend, Silverman plays a mother-of-two living in suburbia who struggles with depression and addiction. To capture this character, the 44-year-old comedian drew upon her real-life experience.

"I've had my experience with depression, having a mother that also had experience with depression and being a child of that and being an adult with that and seeing both sides of it and trying to see what that is," Silverman shared.

WATCH: Sarah Silverman's Mom, Beth Ann O'Hara, Dies

Silverman's mother, Ann O'Hara, died on Aug. 19 at 73, and a few days later, she shared a touching tribute on Twitter. "Wednesday morning my Mom died," she wrote. "She was a know-it-all in overalls and two different colored socks. And defiantly, no bra."

O'Hara touched many lives, having founded the theater company New Thalian Players in Manchester, New Hampshire, where she produced and directed 50 plays over 25 years. For her work, Silverman got to present her mom with a lifetime achievement award at the New Hampshire Theater Awards in 2003.

"One time, she said, 'Sometimes all you have to do is be brave,'" Silverman recalled to ET. "Just meaning sometimes you just have to exist through things and they pass or you get to the other side."

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Silverman keeps remembrances of her mother close by and even wore her overalls during our interview.

"She painted many sets and many grandchildren's nurseries in this," she lovingly remembered. "She was something else. She was one of a kind that one. I may never take these off."

I Smile Back opens Oct. 23. To see Silverman's dramatic turn, watch the full trailer below.