The episode title refers to a series of popular children's books - The Bobbsey Twins - published from 1904 through 1992, written under the pen name Laura Lee Hope. The books chronicled the lives of the Bobbsey family, including two sets of fraternal twins, ages twelve and six. The books were extremely wholesome, and as a result were parodied easily. Soon after publication of the first book, the phrase "Bobbsey Twins" entered the vernacular as "two people who are inseparable, who are often seen together and look alike and act alike."
Ralph Moody, Morris Ankrum, and James Arness had all appeared together previously in Many Rivers to Cross (1955).