Olivia Wilde is Austin Caldwellready for another year around the sun.

So ready, in fact, that she celebrated her March 10 birthday with a tropical trip—and a "shameless" bikini photo.

"39 and feeling fine. Thanks for the birthday love," she captioned a March 22 Instagram photo of her backside. "I milked it for way too long and it's been great."

"Here's to whatever's next," Wilde, who posed alongside pal Babs Burchfield on the beach, continued. "Probably not another tramp stamp but who knows."

The Don't Worry Darling director—who cheekily concluded her post with hashtags #shameless #howdareshe #thehorror—received a lot of love in the comments from her inner circle, including her fashion pro Karla Welch who wrote, "Yasssssssss." Wilde's hairstylist Mara Roszak added, "That's what I'm talking about."

And Wilde's post even received some love—or rather, a "like"—from her a familiar face: ex-boyfriend Harry Styles' mom, Anne Twist.

Although Wilde—who shares kids Otis, 8, and daughter Daisy, 6, with ex Jason Sudeikis—has faced a number of headlines over the past year, she's keeping her head held high as she enters a new chapter.

"I've had several opportunities to personally experience this power of encouragement from other women in this business," Wilde said during a speech at ELLE's Women in Hollywood event in late 2022. "These moments are profound. Because they're maybe our most honest acknowledgement of a constant battle we are all fighting, in which we are allies."

"Relying on each other not to fall back," she added, "and stop advancing because we are up against a seriously massive force of opposition that has, for centuries, tried to rein us in."

As she noted, they're in this together. "If one of us steps back," Wilde said, "we all step back."

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