Sienna Miller Is Pregnant With Third Baby: Debuts Baby Bump With Boyfriend Oli Green at 2025 Fashion Awards

Actor and style icon Sienna Miller is closing out 2025 with joyful news: the 43-year-old star is pregnant with her third child, her second baby with boyfriend Oli Green. Miller quietly turned the 2025 Fashion Awards red carpet at London’s Royal Albert Hall into a pregnancy reveal, debuting a visible baby bump and instantly turning the ceremony into one of the year’s most-watched celebrity moments.

Arriving hand in hand with Oli Green, 28, Miller posed for photographers in a sheer, lingerie-inspired white gown that left no doubt about her news. The ethereal dress, a gauzy Givenchy design, was layered over simple white underwear and cut with a plunging neckline and cape-like tulle back, framing her bump as the centerpiece of the look. Loose, mermaid waves, peachy blush, and pearl-drop earrings completed the red carpet appearance, underscoring why Miller remains a touchstone for bohemian-glam style more than two decades into her career.

The pregnancy marks another milestone for Miller and Green, who have been together since around 2021. The couple already share a young daughter, born in 2023–2024, while Miller is also mom to 13-year-old Marlowe with ex-partner and fellow actor Tom Sturridge. With baby number three on the way, Miller’s blended family continues to grow even as she maintains a busy acting slate and an enduring presence on the fashion scene.

Miller’s London appearance also marked a return to the Fashion Awards after more than a decade away from the event. Her last outing at the ceremony, previously known as the British Fashion Awards, was back in 2013. This year’s comeback, in partnership with Givenchy’s Sarah Burton, served as both a fashion statement and a personal announcement, cementing the night as a key pop-culture moment for 2025.

The news lands against the backdrop of Miller’s increasingly vocal stance on motherhood and age. In recent interviews, she has pushed back on what she describes as a “misogynistic” double standard around women having children later in life, saying she feels like a more grounded parent in her 40s and encouraging women to make family choices on their own timelines. Today’s reveal at the Fashion Awards brings that message into focus: Miller is embracing pregnancy, style, and career on her own terms—and inviting the world to celebrate along with her.