Dolly took to Instagram to post a touching tribute to the late singer, writing: "I was so shocked to hear about Naomi's passing. Naomi and I were close. We were very similar. We were the same age and both Capricorns.
WATCH: Dolly Parton makes heartfelt and urgent plea
"We loved big hair, makeup and music. I have always loved Ashley, Wynonna [Judd's daughters] and Naomi. They've always been like sisters to me."
Dolly then congratulated Naomi and her daughter Wynonna for The Judds' induction into the Country Music Hall Of Fame, adding: "I am sorry I couldn’t be there but I can hear Naomi saying now, 'Oh well, a day late and a Dolly short.'
"Congratulations and condolences are both in order. Just know that I will always love you."
Dolly pictured with Naomi (R) and Wynonna Judd in 1987
Naomi's death was announced by her daughters Wynonna and Ashley, in a statement via The Associated Press. It read: "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."
Naomi's husband Larry Strickland issued a further statement that read: "Naomi Judd's family request privacy during this heartbreaking time. No additional information will be released at this time."
Naomi's last appearance was at the CMT Music Awards
Naomi performed at the CMT Awards last month with Wynonna, 57, with the mother-daughter duo making their first televised appearance as The Judds in over 20 years.
They sang their 1990 hit Love Will Build a Bridge accompanied by a choir of gospel singers, and at one point Wynonna was heard telling her mom: "This is really happening."
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