Nicole Kidman admits these steamy bathroom appliances are key to successful 18-year marriage to Keith Urban

Nicole Kidman says the key to her successful 18-year marriage to Keith Urban is in their bathroom — more specifically, their shower.

The 57-year-old actress admitted that she sings in the shower and, no surprise, so does her country music star husband.

"I also hear Keith singing in the shower, and I’ll hear his new songs forming," Kidman told W Magazine.

"We have a double shower. The double-headed shower: key to a successful marriage. Separate commodes and a double-headed shower!"

'THE...