Marvin Isley, Isley Brothers Bass Guitarist 2.19K Hamilton Nolan 06/08/10 08:10AM Filed to: and now he's dead and now he's dead Obits marvin isley The Isley Brothers Music Marvin Isley, bass player for The Isley Brothers, died last weekend at the age of 56 after suffering years of diabetes-related poor health. He once won millions of dollars from Michael Bolton in a plagiarism lawsuit, which is great. R.I.P.