Mariska Hargitay reveals identity of real father

Mariska Hargitay has opened up about a family secret she's kept for more than 30 years.

Her biological father is not Mickey Hargitay, the man who raised her, but rather a former Las Vegas entertainer named Nelson Sardelli.

At the Cannes Film Festival on Saturday, the Law & Order: SVU actor revealed the news to the audience during the premiere of her documentary My Mom Jayne.

The film tells the story of Hollywood icon Jayne Mansfield's life told through the eyes of Hargitay, who was a young child when her mother died in a car accident.

Hargitay explains in the documentary that she first learned of Sardelli when she was 25. She confronted Mickey, the only father she'd ever known, with the news, but he insisted he was her father, and the two never spoke of it again.

Sardelli, who is now in his late 80s, participates in the documentary, as do his other two daughters - Hargitay's half-sisters.

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

Hargitay 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 also feature in My Mom Jayne.