This week, Keith Urban and Nicole Kidman celebrated their wedding anniversary.

And even after all these years, 13 of them, the celeb couple still seems to have it going on, as evidenced by their classy Instagram posts about each other. As Urban put it so well, "Thirteen years of magic, music, romance, wild adventures, and the ongoing discovery of pure love. Happy Anniversary Babygirl."

But it's not just those public displays of affection on social media that keep Urban and Kidman so happily married. It's what they do in real life.

"The greatest thing our family priest told us very early on in our marriage was, 'Always kiss hello and kiss goodbye,'" Kidman told InStyle in her latest interview with the magazine. "It just keeps you connected.

"We’re just a very close family. We put the time in," she added, "and there’s no taking that for granted."

Urban's tour continues next week with a show in Provo, Utah on July 4 at America's Freedom Festival, and Kidman continues her role as the emotionally conflicted battered wife Celeste Wright on Big Little Lies.