Charlize Theron is not typically one to share much about her private life with the press or on social media. 

But over the weekend, the actor posted a rare photo of her children — Jackson, 8, and August, 5 — to Instagram in honour of National Daughter's Day.

"My heart belongs to these two beautiful powerhouses," she wrote. "I will never be the same."

Watch: Charlize Theron on why she chose adoption. Post continues below.

The Bombshell star's daughters came into her life via adoption.

The 45-year-old had always considered that as her 'first option' for starting a family, something she's traced back to awareness of overcrowded orphanages in her native South Africa.

Theron filed applications in "whatever country" would permit her as a single woman. And after starting the process, it took two-and-a-half years and seven arrangements falling through before she became Jackson's mother in March 2012. 

Their connection was instant.

"I got out of the car and I saw her through a window, and somebody was holding her," she told the podcast Five Things with Lynn Hirschberg. "My heart just jumped out of my body, and I almost couldn't catch it. It was a visceral, emotional feeling."

The same happened with August in 2015, shortly after the end of her three-year relationship with Sean Penn. 

Both her daughters had been born in the United States.

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Happy World Adoption Day from our family to yours!! If we continue to open our minds and hearts, maybe we will find ourselves in a world where every child has the loving family they deserve ❤️ #worldadoptionday

A post shared by  Charlize Theron (@charlizeafrica) on Nov 15, 2016 at 9:45pm PST

"I wanted to believe that somehow my child would find me, in the way that we were just meant to be," she told NPR.

"Everything that I hoped would happen during my adoption process did happen because these two babies were meant to be in my life — and they’re my children."

Theron has described the adoption process as one of the most difficult periods of her life, but acknowledged that many hopeful parents — particularly other single women — struggle even more.

Stigma persists around unpartnered people becoming parents, and several countries (such as South Korea and Sri Lanka) have banned them from inter-country adoption. 

"It’s just so unfortunate. I know so many people who would be incredible parents," Theron added.

"My fight was a little bit easier because of my circumstances, but I would want that for all women who want to share their life."

"I was still talking about her in the press using the wrong pronoun."

Theron has spoken relatively frequently about her girls in recent months.

In May, she posted a photograph to Instagram of an infant Jackson sleeping on her chest on the set of the 2015 blockbuster, Mad Max: Fury Road.

"I became a mum right before we started shooting," she wrote in the caption. "At least my child will forever have the fun fact of 'I spent most of the first year of my life in a war rig.'"

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A post shared by Charlize Theron (@charlizeafrica) on May 14, 2020 at 2:21pm PDT

Last year, she spoke about Jackson being transgender, and how the little girl first expressed her gender identity as a toddler.

"Yes, I thought [Jackson] was a boy, too," she told the Daily Mail. "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."

While Theron is conscious of letting Jackson own her experience ("One day, if she chooses, she’ll tell her story"), the actor has publicly spoken about the importance of using correct pronouns when referring to her.

"I think it became harder for us the older she got that people were still writing about her in the wrong pronouns, and also I was still talking about her in the press using the wrong pronoun," Theron told PrideSource. "It really hurt her feelings."

After all, Theron told the Daily Mail, who her daughters want to be in this world is not for her 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," she said, "and I will do everything in my power for my kids to have that right and to be protected within that."

Feature image: Instagram/Charlize Theron.