In January 2014, Phil Everly – part of The Elverly Brothers – passed away at the age of 74 from chronic obstructive pulmonary disease (COPD).
His son, Chris, said: "My dad was a loving, kind-hearted man and a great father.
"When I lost him to COPD [chronic obstructive pulmonary disease], I lost my best friend."
Chris told the charity, COPD Foundation: "He wouldn't want anyone to go through what he did."
COPD is mainly a smoker's disease, but it can be caused by a rare genetic problem that makes the lungs more vulnerable to damage, the NHS says.
Phil's wife, Patti, said: "COPD took Phil too early – he had so much love and life to contribute to this world.
"We know now that COPD is a genetic disease, even non-smokers can get it.
"However, smoking makes the condition worse, and though Phil stopped smoking in 2001, the lung damage was already done."
The health body points out the "main symptoms of COPD", which includes:
- Shortness of breath, particularly when active
- A persistent chesty cough with phlegm
- Frequent chest infections
- Persistent wheezing.
Emphysema (damaged air sacs in the lungs) and chronic bronchitis (inflammation of the airways) come under the umbrella of COPD.
"See a GP if you have persistent symptoms of COPD, particularly if you're over 35 and smoke or used to smoke," the NHS advises.
While lung damage is permanent, treatment can help slow down the progression of the disease.
If you are a smoker, one of the most helpful things you can do is to become a non-smoker.
Inhalers and medication can be prescribed to help make breathing easier, and surgery or a lung transplant may be necessary.
If you think you need help to stop smoking, visit your local Stop Smoking Service.
Patti said: "Phil Everly was a gifted singer, musician and songwriter, but he was also an amazing husband, a giving and kind person, and a dedicated father and grandfather."
Watch The Everly Brothers: Songs of Innocence and Experience, Saturday August 12 on BBC Two at 9pm.