A Pest in the House is a Merrie Melodies animated short film released on August 2, 1947. It is directed by Chuck Jones and stars the characters of Daffy Duck and Elmer Fudd.The film features a transitional interpretation of Daffy. He is not necessarily the zany, impish interpretation used by Tex Avery and Bob Clampett, nor is he the greedy, self-centered version that Chuck Jones later popularized in the 1950s. As Paul Dini said in the DVD audio commentary for this cartoon: "[In this cartoon, Daffy] is really kind of almost like a sprite. He's just a little, almost elfin creature who's not really out to hurt anybody or has any ill will or malice toward anybody. He's just absolutely out of his mind unhinged."It was only one of three non-Bugs Bunny cartoons from 1947 not to be reissued. The others were Mexican Joyride and Catch as Cats Can (which is the only one of the three that Daffy doesn't appear in).

The cartoon was followed up in 1948 by Daffy Duck Slept Here, wherein Daffy (this time as a fellow guest) again does not let a hotel patron sleep – in this case Porky Pig.