As someone who prides herself on creating powerful, familial connections with her musical community, Kree Harrison has never understood the sentiment of prizing biological family relationships above all else.

"I always heard, 'Blood is thicker than water,' and I could never figure out why that was the saying ... I'd always thought, 'Well, that's bulls--t,'" she remembers, adding that on a literal level, not all of her family members are blood relatives per se.

"I have amazing family -- even my family that's from my sister's dad's side or whatever it may be -- that weren't my actual blood, but I've kind of claimed, my whole life -- that are closer to me than some of my actual, biological family," the singer explains.

And when she looked into the history behind the adage, Harrison realized that the meaning many people ascribe to it today has changed a little from the phrase's original sentiment. "Where it actually came from was war," she adds, "when soldiers were in the trenches together. They called each other 'brother' because they literally shared blood."

That version of the adage rings true for Harrison, who moved to Nashville two decades ago, while she was still a child. As she began to make her way through the ranks of the city's competitive music industry, she needed a support system -- and she created one, from scratch, with other Music City hopefuls who'd also moved to town chasing dreams of country music stardom.

"There's a lot of small-town transplants," Harrison says of the city's musical community. "I think that's part of the reason Nashville is so welcoming, is that we've all looked around and thought, 'Oh s--t, I need a tribe.'"

Now, the singer and American Idol alum is embracing that selected family wholeheartedly with her sophomore project, Chosen Family Tree, out Friday (Aug. 21). The 12-track effort spotlights her longtime musical pals, such as Chris Stapleton, who co-wrote the record's first single, "I Love the Lie." Then there's the album's title track, which features a cameo from her friend John Osborne of Brothers Osborne.

"That's what I'm telling you -- it's all [about musical friendship]," she says with a laugh. "Even at the end, there's a big gang vocal, and I got some of my closest friends to sing on it. That's what the song is. John O. put so much magic on it, no surprise, and I've known John O. since I was 14. He's like an older brother. So, he's just one more chosen fam in there."

All 12 of Chosen Family Tree's tracks were woven out of Harrison's life and personal evolution -- even a cover song that was written two decades before she was born. John Lennon's 1970 track "Mother" makes an appearance on Harrison's new record, and though it's in keeping with the family theme, it wasn't a group effort; on the contrary, the singer says her ability to perform "Mother" is the result of introspective, personal evolution and maturity.

"I've loved that song for so long," she relates. "In a way, my story's very similar to the lyrics, and I've always felt connected to it. But selfishly, I think I was just ready to sing those words.

"It's kind of like therapy for me, being able to say that out loud and know that there are other people in the world just like me, and whenever John Lennon put that song out or wrote that song, that feel the same way," she continues. "I feel like it's my job to continue that."

Over the course of her career thus far, Harrison's confidence and musical expertise have gained momentum, thanks in no small part to the "chosen family tree" surrounding her. But her new album is more than just a group hang or a chance to spotlight her friendships: It's a testament to how family, in every sense of the word, can embolden a person to become the best version of herself.

When listeners hear her album, Harrison's hoping that they'll respond to the authenticity that she has evolved enough to share. "There's so much more of me that I'm putting out on this record than I ever have, more than I've ever said," she reflects.

"There's a lot of little treasures ... and I hope people will see a different side of me," Harrison adds. "But above all, I want it to be worldly. I want it to travel all over, and [I want people to] connect with these songs."

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