Keith Urban’s racy birthday tribute to ‘sexy’ wife Nicole Kidman on her 56th birthday 

They have never been afraid to show their affection for each other.

And on Tuesday, Keith Urban shared a sassy tribute to his wife Nicole Kidman as she celebrated her 56th birthday.

The singer shared a photo on Instagram of Nicole admiring an owl in a tree during a walk and called his wife “sexy.”

To my beautiful, sexy, adventurous, curious, nature loving, owl mocking, artist, wife: happy birthday baby!!!!!! xxxxxx,” he wrote.

The post comes after Keith recently revealed the mantra that ensures he and wife Nicole balance their family life and A-list careers.

The country singer told Fox News Digital that the rule that always works for them is simply, “It always comes first.”

“It’s balanced, so it means sometimes it gets unbalanced, and we just balance it back,” the 55-year-old added.

Keith went on to say it’s not a perfect process, but they keep trying to get it right.

“It’s never perfectly balanced, but we’re getting it back on track,” he said.

He also previously revealed the secret of his marriage, telling on Women’s Day that he “takes care” of their love like a garden.

The singer shared a photo on Instagram of Nicole admiring an owl in a tree during a walk and called his wife “sexy”

“I do the same things I did in the beginning when we started dating,” he said.

Metaphorically speaking, he explained, “It takes care of the garden. If you don’t do the work, the garden starts to overgrow, and then you complain that the garden isn’t that interesting and you look for another garden. I tend this garden.’

He added, “Nicole is also my best friend. I’ve never had anyone in the world know me as well as they do.’

While Keith admits that his relationship – like tending a garden – takes work, he has also said that marriage is easy because he and Nicole “just love being together.”

“We are best friends and we like to do everything together – we are the priority,” he told 2Day FM in September 2016. “Everything else comes after.”

To my beautiful, sexy, adventurous, curious, nature loving, owl mocking, artist, wife: happy birthday baby!!!!!! xxxxxx,” he wrote

Nicole and Keith got married on June 25, 2006, after meeting at an event the previous year.

The couple tied the knot at Cardinal Cerretti Chapel in the grounds of St Patrick’s College in Manly, Sydney.

A-list guests including Hugh Jackman and wife Deborra-Lee Furness, along with Naomi Watts and director Baz Luhrmann were in attendance.

Nicole’s two adopted children, Isabella, 30, and Connor, 28, who she shares with ex-husband Tom Cruise, acted as bridesmaid and usher.

The couple later welcomed daughters Sunday Rose, 15, and Faith Margaret, 12, in 2008 and 2010.

Nicole and Keith got married on June 25, 2006, after meeting at an event the previous year