Charlize Theron has raised her seven-year-old son Jackson as a girl.
The 43-year-old actress has opened up one of her two adopted children - who was introduced to the world as a boy - and the star has admitted that she didn't even know that she'd mixed up her son's gender until the tot told her she was a girl at three-years-old.
She told The Daily Mail: "Yes, I thought she was a boy, too. Until she looked at me when she was three years old and said: 'I am not a boy!' So there you go! I have two beautiful daughters who, just like any parent, I want to protect and I want to see thrive.
"They were born who they are and exactly where in the world both of them get to find themselves as they grow up, and who they want to be, is not for me to decide.
"My job as a parent is to celebrate them and to love them and to make sure that they have everything they need in order to be what they want to be. And I will do everything in my power for my kids to have that right and to be protected within that."
And the 'Tully' star - who also has three-year-old adopted daughter August - "blames" her own mother Gerda Maritz for not knowing "any better".
She added: "You can blame my mom for the fact I don't know any better! You know, I grew up in a country where people lived with half-truths and lies and whispers and nobody said anything outright, and I was raised very specifically not to be like that. I was taught by my mom that you have to speak up; you have to be able to know that, when this life is over, you'll have lived the truth you're comfortable with, and that nothing negative can come from that."
The blonde beauty also admitted that she thinks having a "close relationship" with her children is a "blessing" because she recalls her mother being a strong figure in her own life.
She continued: "I think that having a very close relationship to at least one parent is a real blessing. Growing up as a young girl, I had this great representation in front of me of what you could be as a woman.
"In everything she did in life, my mom did what she had to do and there were no two ways about it. When she got up at six in the morning to milk the cows, she didn't cry about it: she just did it."