Which animated television series that Mark Risley is known for focuses on a group of toddlers?
Mark Risley:  He is best-known for his work on "Rugrats", "The Wild Thornberrys", "The Mr. Men Show", "Space Racers", and Disney's "Yo-kai Watch". Rugrats:  The show focuses on a group of toddlers, most prominently Tommy, Chuckie, twins Phil and Lil, and Angelica, and their day-to-day lives, usually involving common life experiences that become adventures in the babies' imaginations.
Rugrats