Natalie Cole's Cause of Death Has Been Revealed

Natalie Cole's family has revealed what caused the "Unforgettable" singer's death.

Details about the death of Natalie Cole have come to light.

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The 65-year-old Grammy-award winning singer passed away on New Year’s Eve from heart failure brought on by a rare lung disease, her family has revealed.

The daughter of Nat King Cole had been secretly fighting the disease for six years.

Cole was diagnosed with pulmonary arterial hypertension, a rare lung disease that causes shortness of breath, dizziness and sometimes chest pains, her family said in a statement to the Associated Press.

She was diagnosed with the rare disease after she underwent a kidney transplant in 2009, her family said. 

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When she passed, her son and sisters said in a statement: "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."

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