Claydes Charles Smith, a co-founder and lead guitarist of the group Kool & the Gang, has died. He was 57. Smith died in Maplewood, N.J., on Tuesday after a long illness, publicist David Brokaw said Thursday. Brokaw did not know the cause of death. “We’ve lost a member of our family, as well as an infinitely creative and gifted artist who was with the band from the very beginning,” band manager Tia Sinclair said in a statement. Kool & the Gang grew from jazz roots in the 1960s to become one of the major groups of the 1970s, blending jazz, funk, R&B and pop. After a downturn, the group enjoyed a return to stardom in the ’80s. Smith, who was known as Charles Smith, wrote the hits “Joanna” and “Take My Heart,” and was a co-writer of others, including “Celebration,” “Hollywood Swinging” and “Jungle Boogie.” Smith is survived by his six children, Claydes A. Smith, Justin Smith, Aaron Corbin, August Williams, Uranus Guray and Tyteen Humes, and nine grandchildren.