According to Miriam Forman-Brunell, a history professor and the author of Babysitter: An American History, babysitting in its modern incarnation came about in the 1920s, with "the expansion of suburbs for the first time." Parents were more likely to be separated from extended family members that once were relied on to watch children. Coincidentally, the 1920s also gave rise to the notion of a modern teenage girl who cared more about boys, movies and makeup than taking care of kids. To adults, the rise of the teenage girl signaled disorder and fueled anxieties.

As Forman-Brunell writes, because adolescent girls "attended sports events and flirted with men on the street corners, especially in front of the innocent babies they trundled about," the authors of a popular mid-1920s child-rearing manual disparaged adolescent girls and dismissed them as acceptable child-care providers.

Although babysitting first appeared in the 1920s, it didn't flourish as a cultural phenomenon until after World War II. The baby boom created ample jobs for babysitters. Still, though women had enjoyed greater employment opportunities during World War II, parents were hesitant to use a female babysitter. During this period, "parents were very anxious about hiring the girl next door, as has always been the case. It just has so much to do with their perception of teenage girls," says Forman-Brunell.

Even as teenage girls were provoking anxiety in parents, male babysitters were idealized as the perfect solution. During the Great Depression, Forman-Brunell says, unemployed adolescent boys became "saviors to distraught mothers and weary housewives unsatisfied with neighborhood girls."

In glowing descriptions in Parents Magazine from the 1930s, it seemed as if there was nothing boy helpers couldn't do. Some child-rearing experts during the Great Depression believed that male babysitters could go so far as to "restore boyhood" for their young charges. While husbands became depressed due to unemployment or deserted their families, Parents Magazine reassured readers that boys were up to the task of babysitting.

"It's surprising that you would find the entrepreneurial, perfect male babysitter in popular culture, but he's everywhere," says Forman-Brunell, "and he's not burdened by the same expectations that girls are." Being smart, competitive, and business-oriented were all considered positive characteristics of a male babysitter.

By the late 1940s, some Ivy-League schools institutionalized babysitting for male college students. For example, Forman-Brunell writes, male undergraduates at Princeton organized the "Tiger Tot Tending Agency" where, beginning in 1946, "college boys babysat for the children of faculty members and married students for thirty-five cents an hour." One mother who hired male babysitters through the Tiger Tot agency told Princeton Alumni Weekly, "I loved the idea of four strapping young men watching over my baby daughter. Diapers were changed with efficiency and aplomb." Four men came for the price of one babysitter so they could have enough people for a bridge game.