Sienna Miller is growing her family.

The "American Sniper" actress, 43, revealed she was pregnant with her third child during an appearance at the 2025 Fashion Awards in London. Miller, who took the stage alongside British sprinter Dina Asher-Smith to present the award for British menswear designer of the year, wore a white see-through gown, showing off her growing bump.

The barely-there look, which paired white undergarments with a layer of white tulle, provided a pregnancy chic moment for the actress. The dress was accompanied by a set of heels obscured almost entirely by their shag covering.

USA TODAY has reached out to Miller's reps for comment.

Miller is already a mom to two. She shares daughter Marlowe, 13, with ex Tom Sturridge, and a 23-month-old daughter with current partner Oli Green. She and Green, 28, have been dating since 2022. A fellow actor, Green has appeared in recent films "A Good Person" and "Bridget Jones: Mad About the Boy."

The Fashion Awards, held Dec. 2 at the Royal Albert Hall, marks the second time Miller has revealed her pregnancy on a red carpet. In 2023, the actress also opted for a revealing outfit to show off her baby bumb, wearing a two-piece at the Vogue World event during London Fashion Week.

Miller has been open in the past about the pressure she felt in younger years to have children.

In an interview with Elle UK in 2022, the actress revealed she had frozen her eggs, to allow more freedom of choice.

She used to feel "pressure... [about] kids, and should I have more, and why haven't I, and all of that, which is a really loud noise," she told the outlet. "Biology is incredibly cruel on women in that decade – that's the headline, or it certainly was for me. Then I got to 40 and I froze some eggs. 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."

This article originally appeared on USA TODAY: Sienna Miller reveals pregnancy with baby No. 3 in see-through look

Reporting by Anna Kaufman, USA TODAY / USA TODAY

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