Country star Loretta Lynn has lost her oldest daughter, Betty Sue Lynn, to complications from emphysema.

Betty Sue was the first of Lynn’s children with husband Oliver, born when Loretta was just 16 years old. By the time she was 19, she had three children; at 29, she became a grandmother. Loretta always said she never thought twice about having a large family because she herself had been one of eight children.

“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. It wasn’t nothin’ that I didn’t know how to do,” Lynn said.

Lynn eventually had six children–two of which were twins–but lost a son in 1984 when he drowned. Her marriage to Oliver–whom she called “Doolittle”–was notoriously rocky and was chronicled in the film “Coal Miner’s Daughter”, which tells the story of Lynn’s life growing up in Kentucky. She has said that he once left in the middle of her giving birth to one of their children; however, they stayed married for fifty years, until his death in 1996 from complications related to diabetes.

Oh my heart hurts so much for my friend Loretta Lynn. I've just heard her daughter, Betty Sue, passed away this mor… http://t.co/v4r5OJQsSm

— Reba McEntire (@reba) July 29, 2013

Betty Sue Lynn, rest in peace. Loretta Lynn's eldest daughter dies at 64 http://t.co/fNmIloGpDK via @today_ent

— Nicole Justice (@JusticeMack) July 30, 2013

Sending out prayers to @The_LorettaLynn & the Lynn family for the loss of Betty Sue.

— Rodney Atkins (@RodneyAtkins) July 30, 2013