Sienna Miller has always been the quintessential muse of British bohemianism, a woman whose style evolution has mirrored her journey from indie darling to a pillar of refined Hollywood elegance. However, on the night of December 1, 2025, at the historic Royal Albert Hall, Miller shifted the narrative from her past to her future. Standing on the red carpet of the 2025 Fashion Awards, the 43-year-old actress delivered a masterclass in the “cheeky reveal,” debuting her third pregnancy in a breathtakingly sheer Givenchy ensemble. Flanked by her partner, actor and model Oli Green, Miller radiated a sense of serene confidence that only comes with navigating the complexities of life in the public eye. This announcement is more than just celebrity news; it is a celebration of motherhood in one’s forties and a testament to a romance that has defied the skeptics of age-gap relationships.
The Fashion Moment Heard ‘Round the World
The Fashion Awards have always been a stage for high drama, but Miller managed to steal the spotlight with a look that was both daring and soft. Draped in a 100% sheer white tulle gown by Sarah Burton for Givenchy—specifically look 37 from the Spring/Summer 2026 collection—the actress chose not to hide her changing silhouette but to frame it. The empire-waisted mesh dress, paired with simple white underwear and whimsical baby-pink feathered sandals, turned the traditional “maternity look” on its head. It was a visual echo of her 2023 Vogue World appearance, where she similarly used the red carpet as a canvas for her second pregnancy journey.
This wasn’t just a sartorial win; it was a crowning moment for Sarah Burton, who was named British Womenswear Designer of the Year that same night. By choosing a gown that prioritized transparency and ethereal beauty, Miller leaned into a “boho-chic” aesthetic that felt deeply personal. With her hair in loose, salt-water waves and a luminous makeup look crafted by Melina Bisbiki using Charlotte Tilbury products, she looked less like a celebrity making a statement and more like a woman comfortable in her own skin, proving that the most powerful accessory is an authentic life.
Love Without Borders: The Oli Green Connection
Beside her on the red carpet stood Oli Green, the 28-year-old model and actor who has been Miller’s partner since early 2022. Wearing a sharp charcoal gray suit, Green looked every bit the supportive partner, a role he has played with increasing visibility over the last three years. Their relationship, marked by a 15-year age gap, was initially a subject of tabloid fascination. However, the couple has let their longevity and growing family do the talking. Miller has been candid about her initial hesitations, once remarking that she found his youth “annoying” before realizing he possessed a wisdom and stability that transcended his generation.
The pair first made their red carpet debut at the Vanity Fair Oscar Party in 2022 and have since become fixtures at major events, from the quiet greens of Wimbledon to the high fashion of the French Open. In February 2025, they solidified their status as a fashion power couple by appearing in a Frame denim campaign together—the first couple to ever do so for the brand. This second child for the couple (and third for Miller) underscores the depth of their commitment, transforming a “summer romance” narrative into a lasting partnership built on mutual respect and shared goals.
Redefining Motherhood in the Forties
For Miller, this third pregnancy is a chapter in a much larger story about fertility and the “cruel biology” of womanhood. She has spoken openly in the past about the immense pressure she felt in her late thirties to expand her family, leading her to freeze her eggs at age 40. By being transparent about these anxieties, Miller has become a relatable figure for women navigating similar paths. She famously told Elle UK that once she reached 40 and took steps to secure her fertility, the “existential threat” of the biological clock dissipated, allowing her to approach motherhood with a sense of “if it happens, it happens.”
Now, as she prepares to welcome another baby in early 2026, Miller is embracing the “heavenly chaos” of a multi-generational household. She is already a mother to 13-year-old Marlowe, whom she shares with ex-partner Tom Sturridge, and a second daughter born in early 2024 with Green. Balancing the needs of a teenager with those of a toddler and a newborn is no small feat, but Miller has often credited motherhood with putting her life into perspective. She has noted that the realization that someone is infinitely more important than yourself is “incredibly relieving,” providing a grounding force in the often-frenetic world of show business.
A Legacy of Style and Substance
As 2025 draws to a close, Sienna Miller’s influence on the cultural zeitgeist remains as potent as ever. From her early days as a “boho icon” to her current status as a sophisticated actress and producer, she has managed to maintain a rare level of authenticity. Her willingness to share the “unpolished” parts of parenting—the exhaustion, the feeling of failure during the early stages, and the struggle to balance a career with three children—has endeared her to a new generation of fans. She is no longer just a face on a magazine cover; she is a woman defining her own timeline on her own terms.
Looking ahead to 2026, the arrival of her third child marks a new era for the Miller-Green family. While the couple has kept the name and specific details of their first daughter private, their public appearances suggest a unit that is harmonious and deeply connected. Whether she is walking the red carpet in Givenchy or pushing a pram through the streets of London, Sienna Miller continues to prove that life’s most beautiful moments are those that aren’t scripted. Her reveal at the Fashion Awards was a reminder that while trends fade, the joy of a growing family is a classic that never goes out of style.
