Country singer Loretta Lynn's daughter, Betty Sue Lynn, died in Waverly, Tenn., on Monday at the age of 64. Lynn, now 81 years old, has six children, something that she has previously attributed to being raised in a large family herself.

"Well you know I think being one out of eight kids, and I was the second child, you kinda take care of all the sisters and brothers, and it was kind of like me takin' care of my sisters and brothers when I had my first one," said Lynn. "It wasn't nothin' that I didn't know how to do."

Betty Sue was Lynn's eldest daughter. She reportedly died from complications from a battle with emphysema. According to Mayo Clinic, emphysema is a chronic obstructive pulmonary disease that destroys the air sacs in a person's lungs. It reduces the surface are of the lungs, preventing oxygen from reaching the bloodstream. The leading cause of emphysema is smoking.

The loss of Betty Sue is not Lynn's first. According to the Daily Mail, Lynn's son Jack Benny Lynn died in a drowning accident in 1984. He was 34. And, in 1996, Lynn's husband Doolittle Lynn died from complications with diabetes. They were married for 48 years before his untimely death. reports that Betty Sue wrote songs for her mom in the 1960s. According to the site, Betty wrote "Wine, Women and Song," "Before I'm Over You," "The Other Woman," and "The Home You're Tearin Down."

Lynn is perhaps most well-known for her autobiography, which was depicted in the film and song entitled "Coal Miner's Daughter." Her famous friends and country superstars Reba McEntire and Rodney Atkins both expressed that their hearts are with the Lynn family this week.

In a message on Loretta Lynn's Facebook page, she thanked fans for their prayers and support during this difficult time: "The Lynn Family appreciates all of your prayers, love and support of our family's loss. Betty was Loretta's oldest daughter. Betty leaves two daughters, Lynn Markworth and Audrey Dyer."

Betty Sue also has five grandchildren.