This chapter focuses on the developmental issues that impact sleep during infancy and childhood and link to adult sleep. For example, it examines differences in sleep across childhood as well as the relationship of pediatric and adult sleep health and specific issues such as mother–child bedsharing. The chapter discusses the social determinants of sleep for children—for example, increasing screen time and social media involvement, impact of bedtime routines, the mismatch of school hours to the biology of sleep in teenagers (e.g., highlighting that a reason that high schools start at 8 AM in the United States is so that parents can drop them off before they take off on their long commutes to work).