Gordon Bressack, a prolific Emmy-winning writer of animated television series, has died. He was 68.

Bressacks’s filmmaker son James Cullen Bressack confirmed the death in an Instagram post. He wrote, “Words can’t begin to describe how I am feeling right now. You were my mentor, my writing partner, my hero, my best friend, but most of all you were my Dad.”

Bressack wrote for a number of popular cartoon series, including “Animaniacs,” “Jimmy Neutron,” “Teenage Mutant Ninja Turtles” and “The Smurfs.” He won three Daytime Emmys, two for “Pinky and the Brain” and one for “Pinky, Elmyra and the Brain.” He co-wrote the 2017 animated feature “CarGo” with his son, who directed the film.

James Cullen Bressack urged fans to watch his dad’s cartoons in remembrance: “My dad loved to make people laugh, and I’m very grateful his legacy lives on through the many many cartoons he wrote and made. If you like cartoons watch an episode of ‘Pinky and the Brain’ or ‘Anamaniacs’ and have a laugh in his honor. I know its what he would want.”