In her new documentary "My Mom Jayne," now on HBO Max, the "Law & Order: SVU" star opens up about the famous mother she barely had a chance to know.

I couldn’t believe that this truth, this bombshell for me, didn’t ever come to light," says the ‘Law & Order: SVU’ star about going public with her biological father’s identity in an HBO documentary on her mother,

Special Victims Unit" actor created an emotional and revealing documentary about her mother, Jayne Mansfield, who died when Hargitay was just 3 years old.