Who Is Oli Green? Sienna Miller’s Boyfriend, His Career, Age Gap and Their New Baby in 2026

Sienna Miller did not plan to make her baby announcement at a press event for a Prime Video thriller. But when journalists gathered for the promotional rollout of Tom Clancy’s Jack Ryan: Ghost War — premiering May 20, 2026 — she arrived with news that immediately overshadowed the series itself. She had welcomed her third child. Her second with current partner Oli Green. And she was, by her own description to E! News, “madly in love” with her newborn despite functioning on minimal sleep.

The announcement redirected public attention toward Green — a 29-year-old British actor and model who has built a genuine professional career independently of his relationship with one of Britain’s most recognisable actresses, yet who remains significantly less known than the woman he has been with since late 2021.

Who Oli Green Actually Is — Beyond the Age Gap Headlines

Oli Green was born in January 1997 in Britain and trained at the Lee Strasberg Theatre and Film Institute in New York — one of the most respected method acting institutions in the world, whose alumni include some of Hollywood’s most technically accomplished performers. That training detail matters because it positions Green not as a model who drifted into acting but as someone who made a deliberate, disciplined commitment to the craft before his public profile attached itself to Miller’s.

His acting credits span prestige television and mainstream film. He has appeared in The Crown, The Bold and the Beautiful, and The Mosquito Coast, as well as the films A Good Person and Lift. His current project — a role as Paul Joseph in The Gray House — continues a career trajectory building steadily on its own terms. His earliest traceable professional work places him in a music video alongside Kaia Gerber in July 2019, before his relationship with Miller began.

His modelling career operates at the highest commercial level. He has fronted campaigns for Burberry, Gap, and Frame — brands that do not cast unknown faces — and has shot alongside Cara Delevingne and Suki Waterhouse. His most personally significant campaign was a joint Frame denim shoot with Miller, photographed by the brand’s co-founder Erik Torstensson, who is also a longtime friend of Miller’s. That shoot made them the first couple to appear together in a Frame campaign — a professional collaboration that publicly normalised what their relationship represented personally.

How They Met and What the Scrutiny Around Their Relationship Reveals

Green and Miller met at a mutual friend’s Halloween party in late 2021, where they shared a kiss that apparently initiated something neither immediately publicised. They were first connected publicly in February 2022, spotted at a New York Knicks game. Their red carpet confirmation came at the Vanity Fair Oscar Party in March 2022 — one of the most photographed events in the annual celebrity calendar and an unmistakably deliberate choice of venue for going public.

The relationship attracted immediate and sustained commentary about their 15-year age difference. Miller was 44 in May 2026; Green was 29. The intensity of public reaction to that gap — consistently framed as remarkable despite being entirely legal, mutually chosen, and practically indistinguishable from countless male-older celebrity pairings that generate no comparable scrutiny — reflects a specific cultural double standard that Miller has never publicly engaged with at length, which is itself a form of response.

Their appearances together have been consistent and wide-ranging — Wimbledon, the French Open, Glastonbury, British Vogue’s Fashion and Film Party, and the Prince’s Trust Global Gala. These are not the appearances of a couple managing perception. They are the appearances of two people living an ordinary high-profile life together.

Their Family — Three Children Across Two Relationships

Sienna Miller’s family now spans three children across two significant relationships. Her eldest daughter, Marlowe Sturridge, was born in 2012 — the product of her relationship with British actor Tom Sturridge, to whom she was engaged. Marlowe is now thirteen and has grown up largely outside the intense tabloid coverage that characterised her mother’s earlier public life.

With Green, Miller became a mother again in January 2024 — a daughter whose name and precise birth date have never been officially released, a privacy boundary the couple has maintained consistently. Their second child together arrived in May 2026, announced during the Jack Ryan press event with characteristic Miller directness: “It’s happened. I have a tiny baby next door.” No name, no sex, no further detail — just the fact of the child’s existence shared on her own terms and timeline.

That pattern of selective disclosure — confirming what cannot be hidden while protecting what can — reflects a studied approach to celebrity parenthood that contrasts sharply with the fully documented public intimacy that characterised Miller’s earlier years in the British tabloid spotlight.

What Comes Next for Both Individually and Together

Miller’s professional 2026 is anchored by Jack Ryan: Ghost War, which premieres May 20 and represents her most prominent streaming project in several years. Returning to work weeks after giving birth — or at minimum conducting press while newly postpartum — is a logistical reality she has apparently chosen rather than been forced into, which speaks to both her professional momentum and the domestic support structure Green has helped create.

Green’s own career continues developing independently. His Gray House role, his ongoing modelling commitments, and his Strasberg training suggest a performer building toward something more substantial than supporting-cast credits — though the timeline of that development will depend partly on the projects that choose him and partly on how he navigates the sustained public interest that attaches to anyone in Miller’s immediate orbit.

FAQ

How old is Oli Green? 29 years old as of May 2026, born January 1997.

What is Sienna Miller and Oli Green’s age gap? 15 years — Miller is 44, Green is 29.

How many children does Sienna Miller have? Three — Marlowe Sturridge with ex-fiancé Tom Sturridge, and two children with Oli Green.

Where did Sienna and Oli meet? At a mutual friend’s Halloween party in late 2021.

What is Oli Green’s acting training? He trained at the Lee Strasberg Theatre and Film Institute in New York.