‘My Mom Jayne,’ which marks Hargitay’s feature film directorial debut, premiered at Cannes on Saturday, May 17

Mariska Hargitay.Credit : SAMEER AL-DOUMY/AFP via Gett

Mariska Hargitay is opening up about a family secret she’s kept for more than 30 years.

At the Cannes Film Festival on Saturday, May 17, the Law & Order: SVU actress, 61, revealed with the premiere of her documentary My Mom Jayne that her biological father is not Mickey Hargitay, the man who raised her, but rather a former Las Vegas entertainer named Nelson Sardelli.

As Mariska explains in the documentary — which marks her feature film directorial debut — she first learned of Sardelli when she was 25. She confronted Mickey, the only father she’d ever known, with the news, and after he insisted he was her father, the two never spoke of it again.

But it left Mariska with many questions, wondering if she was Hungarian like her father and her brothers, Zoltan and Mickey Jr., or if she was really Italian like Sardelli.

Mariska Hargitay in 2024, Jayne Mansfield circa 1960.John Nacion/Variety via Getty; Silver Screen Collection/Hulton Archive/Getty

The actress opened up further about the revelation about her father in an interview with Vanity Fair. She told the outlet that she went to see Sardelli perform in Atlantic City, N.J., when she was 30 years old, and described his emotional reaction when she introduced herself.

Moved to tears, he said, “I’ve been waiting 30 years for this moment.”

But Mariska said she found herself giving him a tough time and going “full Olivia Benson on him,” referring to her SVU character.

“I was like, ‘I don’t want anything, I don’t need anything from you.… I have a dad, ‘” she recalled telling him, explaining, “There was something about loyalty. I wanted to be loyal to Mickey.”

She also told Vanity Fair that after the momentous meeting with Sardelli, she grappled with “knowing I’m living a lie my entire life.”

Sardelli, who is still alive, participates in the documentary, as do his other two daughters — Mariska’s half sisters.

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In the film, Mariska explains that, at 61 years old, keeping this a secret was no longer necessary.

Mariska also has an older sister, Jayne Marie Mansfield, from her mother’s first marriage, as well as a younger brother, Tony Cimber, from her mother’s third marriage, both of whom are also featured in My Mom Jayne.

Mariska Hargitay and siblings Mickey Hargitay Jr., Zoltan Hargitay and Jayne Marie Mansfield attend Mariska Hargitay’s Star ceremony on The Hollywood Walk of Fame held on November 8, 2013.Albert L. Ortega/Getty

When Hargitay was just three years old, she, along with her two older brothers, survived the car wreck that killed Mansfield, then just 34, in 1967.

The actress told Vanity Fair that once she eventually built a bond with Sardelli and his daughters, she better understood that her mother had returned to Mickey because she knew he would love and provide a stable home life for her.

“I grew up where I was supposed to, and I do know that everyone made the best choice for me,” she said. “I’m Mickey Hargitay’s daughter — that is not a lie.”

Mariska Hargitay, husband Peter Hermann and their kids attend the screening of ‘My Mom Jayne’ at Cannes. BERTRAND GUAY/AFP via Getty

“This documentary is kind of a love letter to him, because there’s no one that I was closer to on this planet,” she noted.

Mariska told Vanity Fair that she and her Sardelli sisters gathered together for a private screening of the documentary in Las Vegas, and recalled how they were overcome with emotion.

“They just wept and wept and wept,” she said. “These two women that I love so much — I made them secrets! It’s so heartbreaking to me.”

Mariska added that sharing her story with the world in the documentary was a way to “unburden all of us.”

Following the film’s premiere screening at Cannes on Saturday, the audience gave a five-minute standing ovation. Mariska was joined at the event by her husband, Peter Hermann, and their three kids.