Daffy Duck, working for a baby-sitting agency, is sent to a farm to sit for a hen who is literally "sitting" on an egg and wants to take a trip. Soon after the hen leaves, the egg hatches, producing a yellow chick whose shape, voice and attitude are similar to that of Henery Hawk.
The chick first calls Daffy "Daddy", then "cousin", "uncle", etc. When Daffy points out he is not a relative, the chick says he is not supposed to talk to strangers, and runs away with Daffy in hot pursuit of his charge. The chick first simply eludes Daffy, and then begins to torment the duck with one violent gag after another (anticipating Home Alone by decades).
In the process, Daffy also incurs the wrath of the barnyard's bulldog, especially as many of the chick's gags lead to Daffy crashing into the dog's house, (re-)splintering it. The film's final joke has Daffy over the dog's knee as he applies a loud and painful spanking to the duck. Daffy calls his agency and tells them he will have to do his next "sitting" job standing up.