KRT file photo Country singers Tim McGraw and Faith Hill have managed to keep equally high profiles during their marriage, which has produced three children.

Tim McGraw has discovered the secret to a happy marriage: become a country music superstar before you tie the knot.

"I think it was helpful that we had a lot of success before we got married," McGraw says of the early achievements he and wife Faith Hill notched before saying "I do" in 1996.

"You've got to be pretty self-absorbed early on in order to succeed, I think, not necessarily in a bad way, but you've got to put everything into it, and I think that's hard on a marriage," says McGraw on the phone from the couple's Nashville home.

What's remarkable about the McGraw-Hill union is the success the couple has been able to maintain separately in an industry notable for lopsided partnerships (see: Waylon Jennings and Jessi Colter, or Whitney Houston and Bobby Brown).

Indeed, they have had eerily parallel careers. Both 40 this year (Hill heads over the hill in September, while McGraw made the leap in May) and natives of the Deep South — she's from Mississippi, he's from Louisiana — each found their way to Nashville after dropping out of college. The pretty blonde and the athletic brunet both broke through in 1994. Each has been blessed with No. 1 hits and armloads of trophies and has sold roughly 30 million albums. While McGraw may have the edge in number of albums released, nine to his wife's seven, Hill did have their three kids, after all.

After 11 years of marriage, the couple have also maintained a spark that is as visible offstage as it is on.

Songwriter Brett Warren, who with his brother Brad has written with McGraw and for Hill, says that chemistry is real. "Man, they have three children, they've been married for 11 years, they fight just like everybody else fights, they love each other just like everybody else does. They don't breathe different oxygen."

"Not only are they the best at what they do, they're good people," says fellow music star Lori McKenna, who was bowled over by the assistance she's been given by the couple's road crew while on tour with them. She has also witnessed firsthand McGraw's penchant for pranks and Hill's mischievous sense of humor.

To which, for the record, McKenna attributes Hill's display of mock outrage at the CMA awards last fall, when she lost to Carrie Underwood. Some viewers were convinced that Hill allowed her inner diva to rear its head. Not so, says McKenna, who was at the ceremony. "Oh yeah, no question (she was kidding). I don't think she's as easy to figure out as people think she is. People think when you're that beautiful and you can sing that well or you're that famous that you're kind of one-dimensional, and she certainly is not."