Ron Palillo, best remembered for his role as the geeky and gawky, yet loveable Arnold Horshack who made up part of the quartet of Sweathogs on the ABC sitcom Welcome Back Kotter, died of a heart attack today at his home in West Palm Beach Florida. He was 63.

Palillo’s death marks the second death of an actor who portrayed a Sweathog on Welcome Back Kotter. Robert Hegyes, who played Juan Epstein, died in late January of this year. The surviving members of those fun-loving high school juvenile delinquents who helped make the show such a success during its original run from 1975-1979 are Lawrence Hilton-Jacobs (who played Freddie “Boom Boom” Washington) and of course, John Travolta, who played Vinnie Barbarino.