One of the earliest challenges for infants and their parents is developing a diurnal sleep--wake cycle. Although the human biological rhythm is circadian by nature, its development varies across cultures, based in part on "zeitgebers" (German: literally "time-givers") or environmental cues. This study uses the developmental niche framework by Super and Harkness to address two different approaches to getting the baby on a schedule. 33 Dutch and 41 U.S. mothers were interviewed when their babies were 2 and 6 months old. A mixed-methods analysis including counts of themes and practices as well as the examination of actual quotes shows that Dutch mothers emphasized the importance of regularity in the baby's daily life and mentioned practices to establish regular schedules for the baby's sleeping, eating, and time outside more than American mothers did. The U.S. mothers, in contrast, discussed regularity less often and when they did, they emphasized that their baby should develop his or her own schedule. Furthermore, actual daily schedules, based on time allocation diaries kept by the mothers, revealed greater regularity among the Dutch babies. Discussion focuses on how culture shapes the development of diurnal rhythms, with implications for "best practices" for infant care.