Dierks Bentley and his wife Cassidy Black, are one of country music's sweetest couples, but they sure took the long way around to forever.

The couple first met at Ingleside Middle School in Phoenix, Ariz., when they attended eighth grade together. Bentley tells People he was "not cool enough" for his future bride at the time.

"I was way too immature and into drinking beer and guns and blowing things up," he says.

"He was just trouble," she adds.

They dated in high school, but he moved to Nashville to pursue country music at age 19, while she wound up across the country in San Francisco, where she landed a job at an advertising firm. But Bentley was still smitten, and he wrote her love letters that he says in retrospect were over the top.

"That's why I married her! I was worried I'd get blackmailed with those letters!" Bentley admits, laughing.

"I did save them and thought I could always sell them on eBay!" she teases.

By 2005, Bentley had established himself in his music career, and he found himself opening for Kenny Chesney. Black came to a show in Las Vegas, and when she walked onto his tour bus, Bentley says, "I just knew."

“It was a weird feeling, and it was right when I saw him," his now-wife told the magazine. "I cried when I said goodbye.”

The couple got engaged in December of 2005, and Bentley instantly surprised her by suggesting they elope to Mexico the very next day, on Dec. 17, 2005. He had even picked out her wedding dress.

"I was speechless — I had just gotten engaged the night before," she recalls. "We got married in a little chapel in Mexico, and it was beautiful and private and real."

The couple have since welcomed two daughters and a son. Evalyn "Evie" Day Bentley was born on Oct. 4, 2008; Jordan Catherine Bentley followed on Dec. 25, 2010; and most recently, they welcomed son Knox Bentley on Oct. 9, 2013. Bentley tells People that the entire family accompanies him on tour now as often as scheduling allows.

"They love traveling, touring. Whenever it's possible, we just drag them out there," the singer says. "I feel like that's my main job really is being a dad."

They have also taken part in his music from time to time. Black starred with Bentley in his sexy video for "Black," and she inspired his single, "Woman, Amen." She also came up with the title for his current album, The Mountain, while Evie made a sweet guest vocal appearance on "Thinking of You" from his Home album in 2012, when she was just three years old.

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