Sienna Miller is now a mom of three after welcoming her second baby with boyfriend Oli Green.
“It’s happened,” Miller, 44, confirmed in an interview with E! News published Monday, May 11. “I have a tiny baby next door.”
While gushing over motherhood, Miller admitted that the transition from two kids to three has been an adjustment.
“It feels like stringing sentences together is a bit challenging,” she teased. “I’m on very little sleep, but I’m madly in love with my baby.”
Miller and Green, 29, are already parents of a baby girl, whose name they have kept private. The Daily Mail broke the news of her arrival in January 2024. The actress is also the mother of daughter Marlowe, whom she welcomed with ex Tom Sturridge in 2012.
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Miller revealed her pregnancy in December 2025 when she debuted her baby bump at the British Fashion Awards, glowing in a sheer white strapless Givenchy gown.
“@siennathing is pregnant!” the official Vogue Instagram account posted at the time. “The star revealed she is expecting her second child at 43 with partner Oli Green at the #BritishFashionAwards this evening, in a @givenchy dress and all.”
Miller and Green have been linked since 2022, though they have mostly kept their relationship out of the spotlight. She made a rare comment about their connection in a June 2024 interview with Harper’s Bazaar.
“I didn’t expect to take it seriously,” she recalled of her initial impression of their romance. “And then quite quickly, I fell in love.”
Miller addressed their age gap too, joking about her reaction to the revelation that Green is 14 years younger than her.
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“I wasn’t like, ‘I’m gonna get a younger boyfriend,’” she recounted. “It was more, ‘F***! Why are you young? That’s so annoying.’”
However, Miller soon realized that the pair’s age difference made them more compatible.
“There is a difference in the way that generation of men respect women,” she explained. “It’s specific to him, he is very wise and well-adjusted, but I do believe it’s also that generation. They have grown up with a slightly more level playing field. I see it in his female friends as well as in the men.”
Miller also gushed about adding to her family with Green at the time.
“I’m in heaven,” she raved of welcoming their daughter. “It’s been a cathartic, healing experience, which sounds woo-woo, but it’s grounded in a way that reflects the life that I want to be living.”
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Amid her relationship with Green, Miller shared in 2022 that she froze her eggs when she turned 40 because of the “pressure” she felt about having more children.
“Biology is incredibly cruel on women in that decade [of their 30s] — that’s the headline, or it certainly was for me. Then I got to 40 and I froze some eggs,” she told Elle UK. “Having been really focused on the need to have another baby, I’m just like, if it happens, it happens. That kind of existential threat has dissipated.”
Later that year, Miller opened up about her persistent desire to expand her family despite setbacks in her personal life.
“I’d invested what felt like the important years in something that was just a bucket with a hole in it of a person. I wasted time. And I felt like time was really my currency,” she told British Vogue in November 2022. “There was a lot of anxiety. Relationships hadn’t worked out — I imagined that I would be married with three kids, being a great mum.”
