Phil Lesh, the founding member of the Grateful Dead, died Friday morning at the age of 84.

The bassist “passed peacefully” surrounded by family, according to an Instagram post.

“Phil brought immense joy to everyone around him and leaves behind a legacy of music and love,” the post read. “We request that you respect the Lesh family’s privacy at this time.”

The statement did not cite a specific cause of death. Lesh, per The Associated Press, had bouts of prostate cancer, bladder cancer, and, in 1998, had a liver transplant necessitated by the debilitating effects of a hepatitis C infection and years of heavy drinking.

The band dissolved after 30 years, with Lesh presiding over a new jazz band called Phil and Friends, often playing shows in the Bay Area in the years before his death.

Lesh leaves behind his wife, Jill, and their two sons, Grahame and Brian.

Per The Associated Press:

Although he was never a prolific songwriter, Lesh also composed music for, and sometimes sang, some of the band’s most beloved songs. Among them were the upbeat country rocker “Pride of Cucamonga,” the jazz-influenced “Unbroken Chain” and the ethereally beautiful “Box of Rain.”

Lesh composed the latter on guitar as a gift for his dying father, and he recalled that Grateful Dead lyricist Robert Hunter, upon hearing the instrumental recording, approached him the next day with a lyric sheet. On that sheet, he said, were “some of the most moving and heartfelt lyrics I’ve ever had the good fortune to sing.”

The band often closed its concerts with the song.