Vidiboobies

Vidiboobies is a television show that Baby Kate likes. D.W. also used to like it when she was younger. When Pal and Kate watch the show, they hear characters speak in engaging and sophisticated language; meanwhile, Arthur and D.W. only hear babble.

Arthur

 * "The Secret Life of Dogs and Babies"

Behind the scenes
It is a reference to Teletubbies.