Cosmo Allegretti, best known for his work as a puppeteer on the popular children’s show “Captain Kangaroo,” has died at the age of 86.

The Associated Press reports that Allegretti, who resided in both Hampton Bays, NY and New River, Ariz., died of emphysema on July 26, though his attorney and friend John Munzel has just decided to make the news public.

While on “Captain Kangaroo,” Allegretti created and voiced a wide range of puppet characters, including the beloved Grandfather Clock and Dancing Bear. He began working on “Captain Kangaroo” as a set painter, but when producers had a problem with a full-sized puppet, Allegretti stepped in to take over the reins. From there, he helped develop several beloved characters including Bunny Rabbit, Mister Moose, Rollo the Hippopotamus, Miss Worm, Cornelius the Walrus, Dennis the Apprentice and others.

During his time on “Captain Kangaroo,” Allegretti also worked as a puppeteer on another classic children’s show, “Mister Rogers’ Neighborhood,” from 1970 to 1971.

Allegretti was also an actor on films like “Prince of the City” and “Sorcerer.”