Congrats are not only in order, they've been shared. And now Nikki Sixx is sharing with fans something that has to be truly treasured and special to him, as Dolly Parton recently sent him a congratulatory thank you letter for his work on her recent hit song "Bygones," which also features Motley Crue guitarist John 5 and Judas Priest frontman Rob Halford.

In a social media post, Sixx remarked, "Gonna have to frame this one," before sharing the typed letter from Parton that appeared on her own branded stationary. The message read as follows:

Hi Nikki,

Well I guess you've heard, we've got a hit record! We're #1 from what I hear on 'Bygones.' You did a fantastic job on that. Thank you for joining us, you made it a lot of what it is. I appreciate you. Rock on!

Love Dolly.

The chart success that Parton is referring to was the chart-topping arrival of "Bygones" on the Mediabase Classic Rock Songs chart. According to a Facebook reel that Parton shared with her fans, this was her second consecutive rock chart-topper. The other, "World on Fire," topped Billboard's Rock Digital Song Sales Chart.

Dolly shared in her posting, "I am so excited to see the response 'Bygones' is receiving! To debut at No. 1 on the Rock charts is such a thrill for me, and it makes it even sweeter to share this with Rob, Nikki and John 5. I also have to recognize my coproducer on the album and cowriter on this song, Kent Wells, who helped me bring this song to life. I am a happy girl today!"

READ MORE: Motley Crue's Nikki Sixx Marks 22 Years of Sobriety in Celebratory Post

Parton is currently promoting her Rockstar album, a massive 30-song offering that saw her enter the rock world after years as a legendary country artist. Parton announced her decision to pursue a rock record after her Rock and Roll Hall of Fame induction last year.

The album features a mix of originals and cover songs with some of rock's biggest names involved. In addition to "Bygones" and "World on Fire," Parton also shared her cover of Heart's "Magic Man" featuring Ann Wilson and guitarist Howard Leese ahead of the new record release.

The album also features guest turns by Steve Perry, Steven Tyler, Joan Jett and the Blackhearts, Elton John, Paul McCartney, Ringo Starr, Mick Fleetwood, Ronnie Van Zant, Artimus Pyle, Gary Rossington, John Fogerty, Sting, Richie Sambora, Kid Rock, Warren Haynes, Stevie Nicks, Waddy Wachtel, Peter Frampton, Chris Stapleton, Miley Cyrus, Pink Brandi Carlile, Kevin Cronin, Debbie Harry, Melissa Etheridge, Lizzo, Simon LeBon, Linda Perry, Michael McDonald, Pat Benatar, Neil Giraldo, Emmylou Harris, Clint Ballard Jr., Sheryl Crow, Ronnie McDowell and the Jordanaires,

In addition to the recent success from working with Dolly, Sixx and John 5 have been working on new music for Motley Crue of late. The pair, along with drummer Tommy Lee and producer Bob Rock, had united in the studio, while Vince Neil recently commented that there are "three brand new Motley Crue songs."

Of those, one is called "Dogs of War," and Motley performed under the moniker "Dogs of War" during their recent club show in London. Another is their cover of the Beastie Boys' "(You Gotta) Fight for Your Right (to Party)," which debuted during that performance. Neil revealed that as he was in Nashville at the time, he did a Zoom call with the producer as the band was working up the material and recorded his vocals apart from the group.

"I don't know if we're going to do a whole album or not. We'll see how these songs go first," added Neil about the new music and what it might lead to. Motley Crue have taken their 2022 "Stadium Tour" and expanded it to hit locations around the world in 2023. Neil also confirmed that the tour will extend into 2024, though the group's touring partners have not been solidified as of yet.

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