The pathophysiology of seborrhoeic dermatitis (SebD) is complex and is likely to be related to an interplay of the microbial colonization of the skin and local immunity. There are also genetic components to the illness. At least two forms of SebD exist, infantile (ISebD), which has onset early in life, and SebD with later onset. We aimed to improve our understanding of SebD by evaluating whether maternal history of SebD is associated with increased risk of ISebD or childhood-onset SebD (CSebD, with onset after 5 years of life). We performed a prospective cohort study of mother-child pairs using data from a large UK primary care electronic medical records database. We analysed 1 023 140 children with linked maternal data. The mean (SD) time of follow-up for the children was 10.2 (7.9) years for a total follow-up of more than 10 million person-years. Proportional hazards models [HRs (95% confidence intervals)] were used to examine the association between presence of SebD in mothers and SebD in the child. Maternal history of SebD was associated with development of SebD [1.99 (1.91-2.09)], ISebD [1.86 (1.74-1.99)] and CSebD [2.12 (1.97-2.29)] in their children. However, ISebD in a child was not associated with that child later developing CSebD [0.91 (0.82-1.01)]. Maternal history of SebD is a risk factor for the development of SebD in children. While we cannot fully differentiate SebD risk due to mother's genetics (inheritance) from a newborn's environment, our results lend credence to the possible role of genetics in SebD. A child with ISebD does not appear to be at risk for developing CSebD.