Astrid Stawiarz/Getty Katie Cassidy
The Arrow alum, 35, opened up to PEOPLE about her "complicated situation" of having three father figures in her life as she attended Friday's 29th Annual Race to Erase MS Gala in Los Angeles.
"I'm directing a film that I actually got Nov. 2019 called Daddy Issues. It's a raunchy comedy about three women in their early 30s trying to learn to grow the f— up but can't due to their dysfunctional relationships with their fathers," Katie said. "I have three fathers so this script, it's so close to home to me ... I was like, there is no one better to direct this film than me."
She noted that she didn't meet her biological father David until she was in the fourth grade, and until then, her inner creativity just felt natural. "And the Cassidy side of my family, it's in my blood, that's in the gene pool. I was born this way," she said.
"The gene pool is so strong. I'm close with my uncles and I talk with them often. And some of the things that my grandfather, who I never met, some of his mannerisms and behavior patterns are similar to what I've done," Katie explained. "My uncle Ryan and my uncle Shaun have shared that with me. And it blows my mind. And even my uncle Shaun, I've been writing more now and producing and directing. And he's sees a lot of my dad in me but he also, I think, sees a lot of himself in me in a way. It makes me feel like, 'OK, I'm not an oddball.' "
Katie's mother, model Sherry Williams, married "wonderful, lovely" ER doctor Richard Benedon when the actress was still young, and the couple raised her together.
"Thank goodness for him because it taught me left and right brain, which is what you need as a director," she shared. "Because as an ER doctor, it's all paperwork, it's all this other side rather than the creative side. And as a director that's what you're doing. You have to have this creative side but then you also have this type A side that's very organized and very on top of s—, which my father Richard was growing up."
"And then my [half] sisters' father is someone I look at as my own because he treated me like his own. So I know it's complicated," Katie added.
"I think it's just a matter of stepping into this space, like this is who I am and this is the family I come from. And I'm proud of it," Katie said. "And I have three dads and I have a complicated situation, but you know what? I'm grateful I'm still here and that we're all still here."
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Prior to his death, David spoke to PEOPLE about the "totally nonjudgmental" bond he and Katie developed over the years. "It's nice when your dad can be your friend," he said in Feb. 2017.
"I wasn't her father. I was her biological father but I didn't raise her. She has a completely different life," the Partridge Family alum noted, adding: "I'm proud of her. She's very talented. It's hard for me to even accept how old she is now, like 30."