The duck appears in the story The Tortoise and the Geese which Mrs. MacGrady tells to D.W. in the episode "D.W., Queen of the Comeback." The story is originally from the Panchatantra, an old Indian collection of fables. The duck appears again in D.W.'s dream later in the episode.
Story[]
The duck makes fun of a tortoise, which is being carried by two geese by holding on to a stick with its mouth. The tortoise cannot resist talking back and falls.
Dream[]
In D.W.'s dream, the duck and tortoise have a tea party in D.W.'s room. They have been quarrelling for two thousand years, because they cannot resist answering each insult with a new insult. The tortoise also chained itself to the duck and the duck lost the key.
The dream convinces D.W. to not insult the Tibble twins back when they tease her about her bad haircut.
Behind the scenes[]
In the original Panchatantra story, the tortoise is teased by human children on the ground, not by a duck.