Dolly Parton offers up her vocals on a new version of Rory Feek's "One Angel," a song that he originally released as a solo performance in March of 2021.

In the newly-released "One Angel," Parton's ethereal vocals gently back Feek's on the track, helping to pull out the complex, painful and deeply personal emotions that inspired the song.

"One Angel" honors Feek's late wife and former songwriting partner, Joey Feek, who died in 2016 after a difficult fight with cervical cancer. The song was written by Sandy Emory Lawrence, a close friend of the couple, who penned the lyrics as an outlet for her frustration and anger about the chemotherapy and radiation that Joey endured before her death.

"So here's three fingers of tequila / One finger for the cancer / One finger for the poison they sent pouring through your veins," Rory Feek sings in the chorus of the song. "One finger for the preacher / 'Cause I don't believe the Jesus / That you love so much would put you through such pain."

The song comes off of Feek's forthcoming Gentle Man album, which is the singer's first-ever solo album and his first full-length project since losing his wife, with whom he performed under the name Joey + Rory. When word that Feek was planning to release a new project reached Parton, the country superstar immediately offered to be a part of it, she explains.

"As soon as I heard Rory was working on this album, I asked if I could contribute somehow. Rory truly is a gentle man. God bless you, Rory," Parton says in a statement.

Parton is more than a friend to the Feek family: She was also a lifelong musical inspiration to Joey Feek prior to the singer's death — the first performance Joey ever gave as a child was one of Parton's songs, Feek explains in a blog post.

"Her very first performance at Cunningham Elementary School back home in Indiana was 'Coat of Many Colors.' She wanted to be Dolly ... to be LIKE Dolly," Feek explains. "And so after high school, Joey packed her things in a horse trailer and moved to Nashville to make her mark in country music the way Dolly did."

Years later, during Joey's last days before her death, she would get a special surprise from Parton, who sent her a taped video message thanking Joey for covering her songs over the years and expressing her admiration for Joey + Rory's own trajectory in country music.

"I'm sorry that you're not feeling good, but I know we have something in common: We both believe in a higher power. We believe that through God, all things are possible," Parton told her. "So you keep praying, and I'll keep praying for you. And I just think that you're wonderful, and I know that God's proud of you. So I wanted to take the chance to say thank you for loving me, and I'll be loving you."

Feek's collaboration with Parton on "One Angel" is one of several duets on the 14-track Gentle Man collection, which also features Vince Gill, Alison Krauss, Lee Ann Womack, Trisha Yearwood and others. Ahead of the project's June 18 release date, Feek also shared another track, "Small Talk Cafe," which features Ricky Skaggs and his fellow musician wife, Sharon White.

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