AUSTIN, Tex. — Willie Nelson’s sister Bobbie has died at the age of 91.

Beloved country singer Willie Nelson posted a tribute to his sister on Instagram on Thursday.

The post reads, “Her elegance, grace, beauty and talent made this world a better place. She was the first member of Willie’s band, as his pianist and singer. Our hearts are broken and she will be deeply missed. But we are so lucky to have had her in our lives.”

The statement goes on to say that Billie died peacefully, “surrounded by family.”

Bobbie was three years Willie’s senior and played piano for more than 50 years with her brother.

The Texas siblings were so close they released a memoir together, titled "Me and Sister Bobbie: True Tales of the Family Band," in 2020.

Bobbie also wrote a children’s book called “Sister, Brother, Family: An American Childhood in Music.”