Plus, the singer tells PEOPLE why he feels like "the luckiest guy on the planet"
So we had to know, are they always that adorable?
“We’re pretty goofy,” Urban, who just released his new album, Ripcord, tells PEOPLE. “I mean there’s no question that that’s what we’re like. Anybody that knows us on a personal level knows that’s exactly what we’re like most of the time.”
With Kidman, 48, performing Carrie Underwood‘s part of the tune, the couple also came up with an adorable nickname for the moment.
“We cranked up the album version and then Nic sang along with it, what we like to call ‘Carrie-okie,'” laughs Urban, 48. “Carrie is from Oklahoma, so the ‘Carrie-okie’ is just hilarious.”
For more from Urban and to read the rest of the country inset, pick up the latest issue of PEOPLE, on newsstands Friday.
The whole sing-a-long is just a snapshot into how much fun the pair are still having as they close in on 10 years of marriage.
“She’s my best friend. I’ve never had anybody on the planet that knows me as well as she does,” says Urban of his wife. “I would love to have been worthy of somebody like Nic, but I was a long way from it when we met. Somehow we just found there was love there, real love. I literally just feel like the luckiest guy on the planet.”
Don’t miss a beat of country music news, photos and videos! Click here to get all this and more in the PEOPLE Country Newsletter.
So what does the luckiest guy on the planet do to celebrate his 10-year anniversary?
“I’m working on that right now,” he says. “It’ll be something intimate and romantic.”