Image Courtesy Rick Diamond/WireImageKacey Musgraves begins her run of shows opening Katy Perry‘s Prismatic Tour Sunday night in Grand Rapids, Michigan. The two struck up a friendship after Katy tweeted about Kacey’s debut hit, “Merry Go Round.” They eventually shared the stage for an installment of CMT Crossroads earlier this year and ended up writing a song that could end up on a future Katy Perry album.

Kacey tells Billboard, “It’s loosely based on Dorothy’s version of The Wizard of Oz, her being in love with the Tin Man, but he didn’t have a heart. And hopefully maybe something will happen with it down the road. Either way, it’s cool to step out of my zone and write for somebody else.”

Kacey is currently climbing the country chart with her new single, “Keep It to Yourself” from her Grammy-winning album, Same Trailer Different Park.

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