US country music singer Naomi Judd has died aged 76.
Judd found fame as part of country music duo The Judds alongside her daughter Wynonna.
In a statement posted on Instagram, her daughters Ashley and Wynonna said: "Today, we sisters experienced a tragedy.
"We lost our beautiful mother to the disease of mental illness.
"We are shattered. We are navigating profound grief and know that as we loved her, she was loved by her public.
"We are in unknown territory."
Judd's career spanned almost three decades and she was awarded a Grammy for country song of the year with the Judds' hit Love Can Build A Bridge.
The Judds were due to be inducted into the Country Music Hall of Fame on Sunday and recently announced they would be going on tour together for the first time in more than a decade.
American actress Kristin Chenoweth paid tribute to Judd on Twitter, she said: "I had the honour of meeting Naomi Judd years ago and she was so incredibly kind.
"Sending love and prayers to Wynonna, Ashley, and the whole Judd family during this time. I never thought she'd go."
Born in Kentucky, Judd was a nurse before forming a band with her daughter.
Judd's youngest daughter Ashley became an actor, known for her roles in such movies as Kiss The Girls, Double Jeopardy and Heat.
American singer Carrie Underwood sent her love to the Judd family, writing on Twitter: "Country music lost a true legend ... sing with the angels, Naomi!!! We're all sending up prayers for the Judd family today..."
Between 1984 and 1991, The Judds released six studio albums and an EP.
During that period, the band also won nine Country Music Association Awards and seven awards from the Academy of Country Music.
In 1991, after a hugely successful career, Judd was diagnosed with hepatitis C. The Judds subsequently announced the band would be coming to an end.
The mother and daughter duo earned five Grammy Awards for hits including Why Not Me and Give A Little Love.
American TV host Andy Cohen paid tribute to Judd, saying: "I loved Naomi Judd. Among her many talents, she was just so much fun, a great storyteller and a wonderful spirit."
Actor Kristen Johnston expressed her sadness after hearing of Judd's death, tweeting: "I'm so sad about Naomi Judd. She was so lovely & warm & fun but the thing I remember best was how proud she was of her daughters, she talked about them the whole time. My heart breaks for her family."
Comedian and TV host Loni Love shared a touching story about her experience meeting Judd.
She tweeted: "Back in 2003 Naomi Judd was a judge on Star search.. she gave me a perfect score and that changed my life.. Thank you Ms. Judd.
"She was a lovely woman and now the world is a little less bright without her. Condolences to her family and fans. Especially Wynonna and Ashley."
In addition to her two daughters, Judd is survived by her second husband Larry Strickland who is also a singer and previously performed with Elvis Presley.
Australian Associated Press
