Singer Natalie Cole has died at 65, the Associated Press reports.Cole's publicist has confirmed the "Unforgettable" legend passed away Thursday night."Natalie fought a fierce, courageous battle, dying how she lived...with dignity, strength, and honor. Our beloved Mother and sister will be greatly missed and remain UNFORGETTABLE in our hearts forever," her son Robert Yancy and sisters Timolin and Casey Cole wrote in a statement to the Associated Press.Daughter of jazz great Nat "King" Cole, Natalie inherited her father's stunning vocals but was determined to forge her own artistic identity, initially shying away from material reminiscent of the King's. Nat King Cole died from lung cancer when Natalie was 15 years old.Ironically, it would be her father's music and vocals that led to her career crescendo. Her 1991 album Unforgettable... with Love, featuring a digital father-daughter title duet, sold 14 million copies and garnered Cole an Album of the Year Grammy Award. Other hit singles include "This Will Be," "Our Love," and "Pink Cadillac." In all, she collected nine Grammy Awards and 21 nominations.Outside the recording studio, Cole's personal life wasn't without its sour notes. In May 2009, Cole underwent a kidney transplant due to hepatitis and other health complications stemming from a heroin addiction, which she chronicled in her 2010 memoir Love Brought Me Back. In recent months, Cole had been forced to cancel tour dates due to an unnamed illness, NBC reports.As news of Cole's death began to spread on Friday morning, friends and fans began paying homage on Twitter.