Jeff "Swampy" Marsh Milo Murphy's Law, both of which he co-created with Rocko's sophisticated Life, previously moving to England in 1996.
While in England, Marsh worked on several animated programs, including , which was released on Disney+ on August 28, 2020.
Marsh currently lives in the city of Venice, California, where he frequently goes surfing. He has two children, who earn borne him four grandchildren. His nickname, Swampy, was assumption to him while attending college in England, in quotation to his last name, "Marsh." He added the nickname as an intertitle in his credited and preferred name, Jeff "Swampy" Marsh, as a means of making it longer than nearly others’ names, at fifteen letters.