Mariska Hargitay on May 18 in Cannes, France.Stephane Cardinale / Corbis via Getty Images
Mariska Hargitay revealed a decades-long secret about her biological father in her new documentary.
The "Law & Order: Special Victims Unit" star is the daughter of the late Jayne Mansfield and Mickey Hargitay. Mansfield died in 1967 when her daughter was 3, while Mickey Hargitay died in 2006.
However, as revealed in the new documentary "My Mom Jayne" and a corresponding interview with Vanity Fair, singer Nelson Sardelli is her biological father, not Mickey Hargitay.
Mansfield and Mickey Hargitay married in 1958, though Mansfield filed for divorce in 1963 and began dating Sardelli. She and Mickey Hargitay eventually reunited months before Mariska Hargitay was born, with her dad ultimately raising her and her siblings after her mom's death.
Reflecting on her relationship with her late father, Mariska Hargitay told the outlet, "He was my everything, my idol. He loved me so much, and I knew it. I also knew something else -- I just didn't know what I knew."
Mariska Hargitay described feeling different from the rest of her siblings -- including two brothers and three half-siblings -- and understood why during her 20s. During that period, somebody showed her a picture of Sardelli, and she recalled instinctually knowing that he was her biological father.
However, when she brought it up to Mickey Hargitay, he denied the claim, and she said she never brought up Sardelli to her father again. Mariska Hargitay didn't drop her suspicion though, and when she was 30, she saw Sardelli perform in Atlantic City and introduced herself to him, causing him to cry.
"I went full Olivia Benson on him," she told Vanity Fair. "I was like, 'I don't want anything, I don't need anything from you .... I have a dad. There was something about loyalty. I wanted to be loyal to Mickey."
Over time, Mariska Hargitay was able to form a bond with Sardelli and his daughters, but she understood why her mom reconciled with Mickey Hargitay.
"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."
She called the documentary "a kind of love letter" to her father "because there's no one that I was closer to on this planet."
The documentary includes cameos from both families, including Sardelli, and her siblings Jayne Marie, Zoltan and Mickey Jr, per Vanity Fair. She also hosted a private screening with her sisters on the Sardelli side, sharing that they "wept and wept and wept" at the film.
"These two women that I love so much -- I made them secrets! It's so heartbreaking to me," she said, recalling a time she introduced them as "family friends" in conversation. "I'm not good with lies. So I also made this movie to unburden all of us."
Mariska Hargitay previously opened up about the lessons she learned from Mickey Hargitay during an appearance on Sunday Sitdown with TODAY's Willie Geist in January.
"High school sports and my father's training taught me how to get back on the horse and have the stamina to do 'SVU.' 'Cause there were hard years," she said. "There were times when I (thought), 'I don't know if I have it. I don't know if I can continue this.' But then, we would do an episode, and I fell so madly, deeply in love with my co-stars. And I was working with such great actors."