John Travolta has expressed his grief over the loss of his former Welcome Back, Kotter co-star Ron Palillo, calling him a great talent and "a wonderful person."

The actor passed away of an apparent heart attack at his Palm Beach Gardens home in Florida on Tuesday morning, aged 63.

His sudden death prompted many fans of the hit sitcom, in which Palillo played nerdy high school student Arnold Horshack, to recall their love for the series online, and now Travolta, who shared the small screen with the star for five years, has paid tribute to his late pal.

A statement from the Saturday Nig...

If you recognize the name Juan Luis Pedro Phillipo de Huevos Epstein then you don’t have to be told who Robert Hegyes was (and you were most likely born before 1975). While John Travolta became the most famous of the Sweathogs when "Welcome Back, Kotter" aired on ABC television in the 1970s, Hegyes’ character "Juan Epstein" was one of the most memorable on the popular sitcom. His forged letters to Mr. Kotter with the closing “Signed, Epstein’s Mother” became a long-running joke on the show and helped propel Hegyes to superstardom even if only for the duration of the series.

The 60 year-o...