See the Letter Dolly Parton Wrote to Sinéad O'Connor in 2003

Though Irish rock and pop legend Sinéad O'Connor was never known for venturing into the country genre, her 2003 cover of Dolly Parton's "Dagger Through the Heart" — part of a tribute album to the country titan — demonstrates an expert, folky and instrument-forward interpretation of bluegrass.

Following the news of O'Connor's death on Wednesday (July 26) at the age of 56, fans from every genre have turned out to express their grief, and their gratitude for the singer's massive impact, musically and beyond. One social media user unearthed a letter that Parton wrote to O'Connor after hearing her cover performance of "Dagger Through the Heart."

"Well, I have always loved you anyhow, but now I love you more," Parton wrote in a letter dated June 25, 2003. "I absolutely love how you sang 'Dagger Through the Heart.' Man alive, I feel that through and through."

"Thank you for being a part of this special project and for giving so generously of yourself and your talent," Parton concluded.

O'Connor's rendition of "Dagger Through the Heart" comes off of an all-star tribute project called Just Become I'm a Woman: Songs of Dolly Parton. Female luminaries from a wide span of genre backgrounds contributed to the project. Other covers included a duet performance of "Coat of Many Colors" between Shania Twain and Alison Krauss, Melissa Etheridge's take on "I Will Always Love You" and Norah Jones' rendition of "The Grass is Blue."

"Dagger Through the Heart" was not O'Connor's only foray into country. She once teamed up with Willie Nelson for a duet rendition of Peter Gabriel's "Don't Give Up," and her 1992 album I Am Not Your Girl included her reinterpretation of Loretta Lynn's "Success." O'Connor titled her version "Success Has Made a Failure of Our Home."

She performed that song as her first number during her infamous October 1992 stop on Saturday Night Live, coming back later in the episode to perform another song — an a capella rendition of Bob Marley's "War" — before ripping up a picture of Pope John Paul II and saying "Fight the real enemy" as a protest against the Catholic Church's alleged cover-up of the sexual abuse of children. (In the decades that followed, the church would go on to face scores of lawsuits and investigations revolving around child abuse.)

O'Connor died on Wednesday after being found unresponsive in a London home, according to CNN. Her death is not being treated as suspicious, and no medical cause of death has been given as of Thursday (July 27). Per the Coroner's directive, an autopsy will be conducted, and the coroner's court states that, "The results of this may not [be] available for several weeks."

The singer's death was also confirmed by her family.

"It is with great sadness that we announce the passing of our beloved Sinéad. Her family and friends are devastated and have requested privacy at this very difficult time," the statement reads.

O'Connor is survived by three living children. Her son Shane died by suicide in early 2022 at the age of 17. O'Connor confirmed his death in a tweet, saying that Shane had "decided to end his earthly struggle" and requested that "no one follows his example."