Keith Urban Honors 'Sexy' Wife Nicole Kidman as She Turns 56: 'Happy Birthday Baby!'

Keith Urban couldn't be more in love with birthday gal Nicole Kidman.

On Tuesday, the country singer paid tribute to his wife on Instagram in honor of her 56th birthday, sharing a photo of her from behind.

In the outdoorsy snapshot, Kidman could be seen wearing a gray long-sleeved shirt and pink baseball cap, her blonde hair tied back into a ponytail, as she peered up at an owl that was sitting on a tree branch.

"To my gorgeous, sexy, adventurous, curious, nature loving, owl spotting, artist, wife: happy birthday baby !!!!!! xxxxxx," Urban wrote in his caption.

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Last October, Kidman celebrated her husband of nearly 17 years with a birthday tribute of her own as he turned 55.

In her Instagram post, the Oscar winner shared a photo from Balenciaga's Couture Collection dinner in Paris, in which the "Wild hearts" singer had his arm around his wife's shoulders and his hand gently cradling her face as they shared a kiss.

"Happy Birthday my love❤️❤️❤️❤️4ever," Kidman wrote in the caption.

The couple first began dating in 2005 and married a year later in Sydney. They share two daughters: Sunday, 14, and Faith, 12.

Urban wasn't the only person close to Kidman to wish her a happy birthday on social media Tuesday, as her good pal Naomi Watts also got in on the fun.

"Happy birthday my darling friend 🎉," Watts, 54, captioned a snapshot of the pair. "Here's to more years of deep friendship and fun adventures."

She added in her birthday tribute to the Big Little Lies actress, "Love you to the moon. So grateful for your love and support. 💥💕"

Watts and Kidman met while working together on 1991's Flirting, which was one of the former's first movie roles. Though they haven't appeared in a film together since, Watts said during a March 2022 interview with Good Day New York that she and Kidman want to collaborate again "so we can have good, lengthy conversations on a daily basis and share meals."

"We've been talking about it for too long — we've gotta make it happen," she said at the time. "Now that we're getting to the age where it's like, we just want to spend more time with each other."