Country singer and "American Idol" judge Keith Urban and his Hollywood starlet wife Nicole Kidman visited their native Australia last week and serenaded patients at the Monash Children's Hospital in Melbourne.

The couple was joined by hospital staff in singing the Christian hymn "Amazing Grace" while Urban played the ukulele. A YouTube video of the impromptu performance has been posted, and has been viewed nearly 50,000 times since Saturday.

While the entire group sang together during the chorus, Kidman took the lead in the first verse – demonstrating her vocal abilities while Urban accompanied. Afterwards, they invited the group to join for a repeat of the chorus, and ended with raucous applause.

Urban was also thankful for grace in a recent interview when he discussed his sobriety from alcohol and cocaine addiction after going to rehab for the third time.

"I was very, very blessed to have Nic call an intervention on me. I had a tight group of friends around me for the intervention. And off I went," he told Rolling Stone Country two weeks ago.

After rehab, he told Oprah that he was using because it felt like something was missing from his life.

"A sense of being centered and connected with something greater than me," he said in a November 2010 interview.

"You can call it what you like, God. There are a million names for it. But, ultimately, for me, it's love. That's the thing that ... I was missing in my life. Love for myself."

The "But for the Grace of God" singer is in Australia for his "Light the Fuse" tour which began last July. The performances are in support of his latest album, "Fuse," released last September. He will be in Australia through the end of June before heading to Canada, and his first concert back in the States is July 17 in Atlantic City. Urban will also make an appearance during the "Good Morning America: Fun in the Sun" summer concert series on July 11.