During her Sunday evening (June 9) CMA Fest set at Nissan Stadium, Maren Morris invited surprise guest Brandi Carlile to the stage for a live performance of "Common," a collaboration between the two artists included on Morris' most recent album, Girl.

Both friends and frequent collaborators, Morris and Carlile are members of new all-female supergroup the Highwomen, an act that also includes Natalie Hemby and Amanda Shires. The foursome debuted their new band at Loretta Lynn's birthday tribute concert in Nashville in April of 2019. They have explained in interviews that they will be joined by a rotating cast of guests as they continue to create new music under the Highwomen umbrella, and that as a group, they seek to create a country-leaning collective that empowers all women.

Even without her duet with Morris and the inception of a new band, Carllile -- a perennial Americana favorite -- has rocketed into mainstream success in 2019. In January, she picked up several Grammys, cementing her all-genre appeal. At the 2019 ACM awards,  she proved she could shine on a mainstream stage, too, duetting with Dierks Bentley on the twangy "Travelin' Light." Later in the year, Carlile announced that she would be producing a new album for country mainstay Tanya Tucker. Even as she found new ways to expand the genre, in 2019, the singer found her way even closer to its heart.

"I started out singing country music as a child, and all the way up through my teenage years," Carlile explained backstage before her Sunday night performance. "I've never really been far away from it. I consider country music, country and western music, Americana, American roots music just to be the great American story. So I'm telling that story, whether I'm playing with Tanya or the Highwomen or the Secret Sisters."

Still, Carlile acknowledges that 2019 has been an extraordinary year. "I feel really embraced by the [country] community right now, and for that I am unspeakably grateful, especially as a LGBTQ artist," she adds.

Aside from her duet with Carlile, Morris delivered a rousing solo set that included tracks from her new album as well as fan favorites like her first hit song, "My Church."

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