When country superstar Tim McGraw hits the road, he's the first to acknowledge that boys will be boys! However, when he's on tour with wife, Faith Hill, he says things tend to be more along the path of the straight and narrow. "There's less nudity involved while running the halls when my wife is here than when she's not," Tim tells PEOPLE magazine. "And getting tattoos on the road is always possible [when she's not around]. I don't know if Faith would be real crazy about another one, though!"

When Faith is on the road with her hubby, their three daughters -- Gracie, 13, Audrey, 11, and Maggie, 8, are usually along for the ride -- so Tim and his band tone down the more "adult" conversation. "Everybody pays attention to the language [when the girls are on the road]," Tim says. "I grew up in locker rooms playing sports, and when I get out on the road, it can get pretty bad! We've aged gracefully, so we're better at putting a muzzle on ourselves. We're more sophisticated about [cursing] now."

On Oct. 6, Tim and Faith will celebrate their 14-year wedding anniversary. Shortly after they started seeing each other, the couple came up with their "three day rule" which keeps time spent apart to no more than just a few days. That rule is something the two have proudly adhered to all this time. "You can get the blahs from waking up on the bus every day doing the same routine," Tim explains. "I think having your regular life, too, keeps it fresh. It's like you're going to work."

Tim is currently out on the road with Love and Theft and Lady Antebellum on the Southern Voice tour. The video for his latest single, 'Still,' was released last week.

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