Bobbie Nelson, 91, peacefully passed away on Thursday morning, according to a statement from Willie Nelson's publicist. She was a pianist and singer who performed with her brother for more than five decades.

Bobbie was an original member of the Willie Nelson and Family Band and integral to helping create her brother's unmistakable sound. While she spent most of her time behind the piano blending in with the other players, she occasionally led the band and wowed crowds with her skillful playing.

Bobbie was about two years old than her little brother, and the pair were raised by their grandparents in Abbot, Texas.

"My grandfather had said to me when I was learning to play the piano: You know, if you really work at this, you could earn your living playing music one day," the provided statement quoted Bobbie as saying. "And I never forgot that."

The siblings were teenagers when they started playing in honky-tonks together alongside Bobbie's husband Bud Fletcher and their father, Ira Nelson, who played guitar. Bud died in a car accident, and Bobbie quit the band to care for their three sons and attend business college. When she graduated, the Hammond Organ Company hired Bobbie to help in the office and demonstrate the company's instruments. With her children older and her feet wet again as a performer, Bobbie began playing shows again and could eventually earn a living as a pianist in Austin and Nashville.

"It was a fabulous thing because I was back really playing music again, not just demonstrating and selling organs," she explained. "I was very happy to be able to sit down and just play from my heart and soul."

Willie invited Bobbie to join his band in 1972 when he signed his record deal with Atlantic Records.

"I was just so happy to be playing music with Willie again," she said.

Bobbie released her debut album "Audiobiography" in 2007, and two of the 12 songs included Willie singing and playing with her.

She was recently featured on "The Willie Nelson Family" (2021, Legacy Recordings), a collection of country gospel-flavored songs performed by Willie's Family Band.

Willie and Bobbie also wrote two books together that were published in the last two years -- the memoir "Me and Sister Bobbie: True Tales of The Family Band" and "Sister, Brother, Family: An American Childhood in Music."