Keith Urban's Uncle Reveals A Dark Secret About His Nephew & Nicole Kidman's Marriage — Will It Last?

Keith Urban, 48, and Nicole Kidman, also 48, have had their fair share of marriage problems, but his uncle, Paul Urbahn — whose name is still spelled with an "h" that Keith decided to nix — is blowing the lid off about the famous pair's union.

"No one thought it would last," his uncle told RadarOnline about Keith and Nicole. Even worse, Paul claims that the country singer relapsed right after their big day.

"After the wedding, Keith went back to dope and booze," Paul said. "I thought [their marriage] would fall apart after that point, but he went to rehab and managed to kick it."

That was the third time the American Idol singer checked into rehab for addiction, which his uncle blames the relapse on being married to an A-lister like Nicole.

Even worse, Paul claims the crooner's struggle to stay sober caused him to steer clear of his family — even his father before he died of prostate cancer last December. "[Keith and Bob] weren't close in the end, living that far away for so long," Paul said, also adding that even "Nicole wasn't close to her in-laws."

As Star previously reported, this isn't the first marriage strife for the couple. Just last August, Keith was allegedly caught alone with country singer Kelsea Ballerini on his tour bus.