Sia has shared that she adopted her two sons after seeing one of them in a television documentary.
It comes after the 44-year-old shared earlier this year that she had become a mother after taking on two teenagers.
Speaking to Vogue Australia, the singer said: "I am obsessed with reality television and documentaries, and I watched a documentary and saw my son I was like: ‘What? Like, he doesn’t have anybody. Oh my God. I’m going to find him and I’m going to be his mummy.’
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“And so that’s what I did."
After tracking him down, Sia also adopted his friend as the pair left foster care due to their age.
Back in May she told US radio station SiriusXM Hits 1: "I actually adopted two sons last year. They were 18, they're both 19-years-old now. They were ageing out of the foster care system and yeah, I love them."
Earlier this year, the Chandelier hitmaker also revealed one of her sons had welcomed two babies, making her a grandmother.
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She told Zane Lowe’s Apple Music Podcast: “My youngest son just had two babies. I’m a f***ing grandma!”
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Despite mentioning her sons in the Vogue Australia interview, in August Sia vowed not to speak about her children's private lives again after sharing the news of her son’s babies.
“While I didn't get into trouble for blabbing about his [her son's] children - I was peeing, which is where I have my best thoughts, and I realised that it was not my news to share with the world,” she remarked on Australian radio show The Kyle and Jackie O Show.
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