It's been 28 years since Dolly Parton, Linda Ronstadt and Emmylou Harris released their Grammy-winning Trio record, but Parton says that a new collection of tunes from the three singers will soon be available.

“We’ve been trying for years to put out the thing that we had in the can and repackage the things that we did,” Parton tells CMT. “Emmylou has been working at this for a long time. We thought it was coming out two to three years ago — actually even before that — but I just got a note from Emmy and Linda saying that they had signed off on it, and so it is gonna happen. I don’t have a date, but it’s supposed to be coming out this year.”

The new project will be especially meaningful given that Ronstadt's ongoing battle with Parkinson's disease has left her unable to sing.

“I can’t get to the note,” Ronstadt says. “I can’t make any quality sound. I can’t arrange pitch. I might aim for a note and hit another one. It sounds like shouting.

“My life is very different,” she adds. “That’s all there is to it.”

Trio won a Grammy in 1987, for Best Country Performance by a Duo or Group. The threesome also released Trio II in 1999, and although that album, which was recorded in 1994, did not produce any hit singles, a song from Trio II, "After the Gold Rush," won the three women another Grammy, for Best Country Collaboration With Vocals.

Harris, Parton and Ronstadt are all keeping busy. Harris is releasing an album with Rodney Crowell, The Traveling Kindnext month. Ronstadt's memoir, Simple Dreams — A Musical Memoir, was released last year and is available for purchase on Amazon. And Parton is focusing much of her attention this year on the 30th anniversary celebration of her theme park, Dollywood, which will include nightly fireworks displays and four performances at the park by Parton herself.

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