Sienna Miller is bumping along!

The model debuted her budding belly in a brown string bikini while vacationing in Ibiza Saturday.

The pregnant 41-year-old, who accessorized with red feather earrings, a gold necklace and matching bracelets, was photographed walking on the beach over the weekend with her stomach on display.

Miller’s reps have yet to respond to Page Six’s request for comment.

Last month, the actress sneakily showed her baby bump in a colorful bathing suit while boating in St. Tropez with her boyfriend, Oli Green, and her 11-year-old daughter, Marlowe.

Miller gave birth to her eldest child in July 2012 while dating Tom Sturridge.

She and the “Sweetbitter” alum, 37, called it quits three years later.

After Miller was spotted getting cozy with Green, 28, in March 2022, she opened up to Elle UK about her future family plans.

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“I got to 40 and I froze some eggs,” the Golden Globe nominee told the outlet in April of that same year.

“Having been really focused on the need to have another baby, I’m just like, ‘If it happens, it happens,'” she continued at the time. “That kind of existential threat has dissipated.”

Prior to making that decision, the “pressure” to conceive another child felt like “really loud noise.”

Miller explained, “Biology is incredibly cruel on women in that decade – that’s the headline, or it certainly was for me.”

The notoriously private star did not speak to her relationship with Green at the time.

She remains tight-lipped about motherhood as well and has refrained from showing the little one on social media.