John Travolta has said he will miss Welcome Back, Kotter co-star Ron Palillo, who died Tuesday at the age of 63.

“Ron was a wonderful person and talent,” Travolta said in a statement, “and helped catapult Welcome Back, Kotter to great success. We will miss him.”

Palillo authored two children's books, wrote a full length play and appeared in numerous Broadway productions, however he is best known for playing high school student Arnold Dingfelder Horshack on the ABC comedy sitcom.

According to, Palillo died of a sudden heart attack. The openly gay actor was found by his longtime partner Joseph Gramm.

In 1992, Palillo told PEOPLE magazine that his work on the stage had helped him overcome a crippling depression.

He lived in Palm Beach Gardens, Florida. For about the last three years, Palillo had been teaching at the G-Star School of the Arts in West Palm Beach, according to