He's a big brother now! Charlize Theron steps out with son Jackson for first time since it emerged she has adopted a little girl

He recently became a big brother - and he even has the top to prove it.

Charlize Theron and her son Jackson have been spotted for the first time since it emerged a new member has joined their family.

On Saturday news broke that the actress, who turns 40 on Friday, had adopted a little girl named August.

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Big brother: Charlize Theron and her son Jackson have been spotted for the first time since it emerged a new member has joined their family

Big brother: Charlize Theron and her son Jackson have been spotted for the first time since it emerged a new member has joined their family

According to TMZ, the South African beauty took custody of the African-American tot last month, after working with with a US adoption agency for six months.

It is the superstar's second child, after she adopted three-year-old Jackson from her home country in 2012.

And the boy couldn't have looked prouder and he walked hand in hand with his mom in LA on Monday wearing a top bearing the words 'Big Brother Jackson' on the chest.

Growing family: On Saturday news broke that the actress, who turns 40 on Friday, had adopted a little girl named August

Growing family: On Saturday news broke that the actress, who turns 40 on Friday, had adopted a little girl named August

Process: According to TMZ , the South African beauty took custody of the African-American tot last month, after working with with a US adoption agency for six months

Process: According to TMZ , the South African beauty took custody of the African-American tot last month, after working with with a US adoption agency for six months

The now-mother-of-two looked her usual stylish self, with a black and white patterned see-through skirt and matching sandals with a black tank top.

Charlize has candidly spoken about her desire to adopt since she was a child.

She previously said: 'I've always known I wanted a family. I don't think my mom could wait any more!'  

Proud: The boy couldn't have looked prouder and he walked hand in hand with his mom in LA on Monday wearing a top with the words 'Big Brother Jackson' on the chest

Proud: The boy couldn't have looked prouder and he walked hand in hand with his mom in LA on Monday wearing a top with the words 'Big Brother Jackson' on the chest

Fab: The now-mother-of-two looked her usual stylish self, with a black and white patterned see-through skirt and matching sandals with a black tank top

Fab: The now-mother-of-two looked her usual stylish self, with a black and white patterned see-through skirt and matching sandals with a black tank top

Opening up about a letter she penned as a young girl, she revealed: 'It said, "Would you please take me to an orphanage, so that I can go and adopt a baby?"

'I always knew I would adopt. Always.'

Back in May, the blonde beauty admitted she was 'open' to having more children, but gave no hints she was planning on adopting again.

Awkward! On Wednesday the Charlize and ex-fiance Sean Penn had a rather awkward looking reunion in Cape Town as they reshot scenes for his film The Last Face, which stars Theron.

Awkward! On Wednesday the Charlize and ex-fiance Sean Penn had a rather awkward looking reunion in Cape Town as they reshot scenes for his film The Last Face, which stars Theron.

If looks could kill: the Monster star, who called off her engagement to 54-year-old Sean Penn two months ago 

If looks could kill: the Monster star, who called off her engagement to 54-year-old Sean Penn two months ago 

Asked if she would like more kids, she said: 'Yeah. I mean, I'm so open to anything in my life. I was never like, 'Oh god no just one.' I was always kind of open to whatever kind of happens. 

The momentous occasion follows heatache for the Monster star, who called off her engagement to 54-year-old Sean Penn two months ago.

On Wednesday the two had a rather awkward looking reunion in Cape Town as they reshot scenes for his film The Last Face, which stars Theron. 

Ups and downs: Penn and Theron, who had been friends for two decades, split in June after nearly 18 months together

Ups and downs: Penn and Theron, who had been friends for two decades, split in June after nearly 18 months together

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