Thomas Rhett's newest single, "Life Changes," is arguably his most personal song to date. Each of the three verses describes a pivotal moment that shaped his life: his days as a casual songwriter, back before he made it big in country music; marrying his childhood sweetheart, Lauren; and the process of adopting his daughter, Willa Gray, and the birth of his second child, Ada James.

As a single, "Life Changes" is quickly climbing the charts, but Rhett says that he wrote the song not knowing whether it would even make it onto his record. "It was written super late in the album-making process," he says. "That song was written out of ... wanting to talk about a few moments that we felt were super pivotal to where we were at today."

"That song is definitely one of those songs that's just in-the-moment, and I kind of just wrote it because it was what I was going through," Rhett added backstage to The Boot and other media outlets at the 2018 CMA Music Festival. "I never in a million years thought it would be a single. So I'm super excited that we get to put it out."

As "Life Changes" has become an unexpected hit for Rhett, the singer is starting to contemplate the possibility that he may be performing the song for years to come, through additional pivotal life moments. So, how does he plan to keep the song up to date with his life?

"I'm gonna have to write some new verses!" Rhett says with a laugh. "Probably in five years, I'm gonna be talking about my sixth kid that's on the way. More than likely."

In addition to performing during CMA Fest 2018, which took place in early June, Rhett and Kelsea Ballerini will be co-hosting a TV special filmed during the four-day event. The TV special will air on ABC on Aug. 8.

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