Calvin may have been only six years old, but he already had a sworn arch-enemy: Rosalyn, the babysitter who sent him to bed at 6:30. Although Calvin often clashed with his neighbor Susie, his rivalry with Rosalyn became one of the strip’s most effective recurring comedy setups.
Rosalyn first appeared in May 1986. In her earliest weekday storyline, she locked Calvin in the basement for hours, presenting a much harsher version of the character than the one readers would later see. Over time, the dynamic changed. Calvin became the main source of trouble, while Rosalyn’s role was generally limited to enforcing his bedtime.
Many of Rosalyn’s appearances unfolded across several days, allowing Bill Watterson to build longer comic stories around their conflict. In one 1989 storyline, Calvin tricked her into leaving the house, locked the door, taunted her from the windows, watched television and ate an entire package of Oreos.
Her most memorable story appeared earlier that year in the storyline later associated with the collection Calvin and Hobbes: The Revenge of the Baby-Sat. After learning that Rosalyn needed to study for a science test, Calvin declared an evening of revenge. He stole her notes and locked himself in the bathroom, threatening to flush them.
Rosalyn responded with one of her funniest lines in the series: “Calvin! Open this door, or your parents will never find your remains!” She eventually outsmarted him by pretending to give up, then recovering the notes when Calvin opened the door. Calvin later admitted that he had not actually flushed them.
Rosalyn’s final appearance offered a different ending to their rivalry. Instead of sending Calvin directly to bed, she proposed playing a game in exchange for good behavior and an extra half-hour before bedtime. Calvin chose Calvinball, his constantly changing game, and Rosalyn eventually embraced its shifting rules. She even created a “Babysitter flag” to end the match, after which Calvin went to bed peacefully.
The story ran in September 1995, three months before Watterson ended Calvin and Hobbes. It gave Rosalyn and Calvin a rare moment of cooperation while preserving the long-form storytelling that had made their rivalry one of the strip’s most memorable recurring conflicts.
Sources: Polygon.