Chris Ethridge, the bass player who lent his musicianship and songwriting to the Flying Burrito Brothers, the International Submarine Band and others, has died at 65, Rolling Stone reports.

Ethridge co-founded the Flying Burrito Brothers with Gram Parsons, playing on "The Gilded Palace of Sin"; he later co-wrote Parsons' solo track "She." Over his lengthy career, he performed with musicians including Ry Cooder, the Doors, Graham Nash, David Crosby and Willie Nelson.

Nelson, who enlisted Etheridge for his Family Band, addressed the passing on his Twitter page on Monday.

"WN&F are sad to hear of the passing of Family member & friend Chris Ethridge he was a talented musician & we were honored to call him Family," Nelson tweeted.

Ethridge was reportedly hospitalized as of last week, though the circumstances of his death have not yet been made public.