Possible Clues:

• Bluto and Pluto
• 18-Across and others
• Pixar characters
• Wimpy and Stimpy
• Animated figures
• Arthur and Garfield, for two
• Bugs and his buddies
• Tweety and Daffy, e.g
• Huey, Dewey and Louie, e.g.
• The Simpsons, e.g.