For Dolly Parton, as for many others, Christmas is a time to spend with family, and with friends who have become like family. So when she was working on her new Christmas album, A Holly Dolly Christmas, it only made sense to ask a few special guests to join her on the record.

A Holly Dolly Christmas features duets with longtime friends Willie Nelson ("Pretty Paper") and Billy Ray Cyrus ("Christmas Where We Are"); Parton's goddaughter Miley Cyrus ("Christmas Is"); and the country icon's brother, Randy Parton ("You Are My Christmas"). It also features newer pals Michael Buble ("Cuddle Up, Cozy Down Christmas") and Jimmy Fallon ("All I Want for Christmas Is You"), and bluegrass icon Rhonda Vincent and her brother Darrin play on "Christmas on the Square."

Beyond those guest appearances, two additional family members were involved with the project: Parton's niece Jada (daughter of her sister Freida) helped pen the Billy Ray Cyrus duet, while her niece Heidi (Randy's daughter) sings backup vocals on "You Are My Christmas."

Randy, Parton shares, was "our Christmas baby," born to her parents in December; in fact, her mother often joked that he was a real-life substitute for the lifelike baby doll Parton and her siblings asked for as a gift, which her parents couldn't afford. His inclusion on "You Are My Christmas" adds another possible interpretation to the festive love song, as well.

"It can be interpreted in all ways: as a love song, as a brother song and as a Jesus song," Parton explains of the track, which opens with the lines, "When I think about what Christmas means / The celebrations and the scenes / Things that I hold dear and true / I mostly think of you."

But it was a chance to sing with Fallon that prompted Parton to call up her friends and family for A Holly Dolly Christmas in the first place. "I didn't think about doing a bunch of duets at the start," she admits; rather, it was the idea of getting to perform "All I Want for Christmas Is You" with Fallon -- finally -- that got the ball rolling.

"When I was on [The Tonight Show] a couple of years ago around the holiday season, he had asked me if I would sing with him, Mariah Carey's song ... and I didn't know it good enough to sing it, and I didn't want to mess it up," Parton shares, "so of course I said no ... and it really bothered me."

Parton's a fan of Fallon's frequent collaborations with other artists, however goofy they may get, so she called him up and convinced him to do the song for this record. "Then I got to thinking, 'Well, maybe I'll get all these other guys to sing with me,'" she adds.

"It was just one of those perfect storms," Parton continues, "where everything fell like it was supposed to."

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