Willie Nelson's younger brother, Ira Doyle Nelson Jr., passed away on Wednesday (April 15) at the age of 77.

Nelson Jr., who went by Doyle, died of natural causes, according to a statement that the country legend posted to his Facebook page.

"Doyle spent his life in many transportation-related jobs, including driving tour buses for folks such as Jon Bon Jovi, Van Halen, John Fogerty and his brother Willie," the statement reads. "He spent several years serving transportation needs for the television and film industry. He was a gentle man who will be dearly missed."

Nelson shared several photos of his brother with the statement as well, including one with the whole family.

While much is unknown about Nelson's now-deceased brother -- who was named after his father -- the musician and his sister Bobbie have been quite open about their childhood in Abbott, Texas. Since their mother moved away soon after Willie Nelson was born and their father remarried and also moved away, they were raised by their paternal grandparents.

“We grew up working on farms and making our school money picking cotton, baling hay, whatever. It was a great way to grow up,” Willie Nelson says. “We learned a little about everything in Abbott. There was no laws up there, so we could pretty well do what we wanted to do, as long as we lived through it, and fortunately we did.”

Plus, a love for music was instilled in them at an incredibly young age -- and those are cherished memories for the siblings.

“Some of my, really, earliest memories, besides walking through the field, would be us learning music, our grandparents showing us music,” Bobbie Nelson shares. “Our grandfather was very much into gospel music — our grandmother, too — and I was trying to learn to play the pump organ. I remember Daddy Nelson showing Willie how to play the guitar, and he taught [him] how to sing so that when he’d go to school, he could sing for the kids.”

Bobbie and Willie Nelson have often shared a stage together, and since their brother Ira was a tour bus driver, it's safe to say that a love of music ran in the family.

The Boot expresses our condolences to the entire Wilson family on the loss of Ira.

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