Stu Rosen, an Emmy and Peabody Award-winning force in children’s programming died early Sunday morning after a battle with cancer. He was 80.

“This is a very sad day for my family and I. My wonderful, colorful, fantastic cousin, Stu Rosen died this morning,” wrote Rosen’s cousin Donna Siegel on Facebook. “My heart is broken and I’m sure anyone who has ever met him feels the same way. What a character he was.”

She continued, “He is the one I wrote about a few months ago that I gave a birthday party for….but it was really a going away party because he was dying of cancer. I told you all that it was the best party I have ever given.”

Rosen’s was into the industry was as a production assistant at KCET before creating and serving as the co-executive producer of the children’s television program Dusty’s Treehouse. Rosen starred as the titular Dusty in the series that ran from 1970-1980 and featured the puppets of Tony Urbano. Cut from the same cloth of shows like Mister Rogers’ Neighborhood and Captain Kangaroo, the series featured animal puppets and covered topics like music, school, politics, kindness and behavior. Dusty’s Attic, a forerunner of Dusty’s Treehouse featured future Oscar winners Steve Martin and Paul Williams. Dusty’s Treehouse went on to win eight Emmys and later appeared in reruns on Nickelodeon.

Related Story Robert L. Lasky Dies: APA Co-Founder Was 91

Rosen served as governor of the children’s TV branch of the Television Academy. On the directing side, he helmed animated series such as MASK, Hulk Hogan’s Rock ‘n’ Wrestling, The Legend of Prince Valiant, Biker Mice from Mars as well as the episodes of Teenage Mutant Ninja Turtles in 1987. He also voiced directed and lent his voice to the iconic Jim Henson series Fraggle Rock.

His credits included an array of popular animated series such as Batman: The Animated Series, The Pirates of Dark Water, X-Men, Spiderman: The Animated Series and Superman: The Animated Series. He also directed and voiced Phantom 2040 which included the talents of Margot Kidder, Ron Perlman, Leah Remini, Mark Hamill, Debbie Harry, Rob Paulsen and Paul Williams. On the live-action side, he appeared in Rome and The Huntress.