Prenatal alcohol exposure (PAE) can lead a constellation of physical dysmorphology and neurodevelopmental impairments that are captured under the diagnostic banner of “Fetal Alcohol Spectrum Disorder” (FASD). For many children with PAE there is ongoing exposure to environmental adversity that may also contribute to their neurodevelopmental impairments. A current challenge in the literature is to disentangle the effects of PAE and exposure to adversity on neurodevelopmental impairments in young children. This thesis focuses on the neurodevelopmental domain of sleep. Disrupted sleep is a recognised but poorly understood domain of impairment in children with FASD. It is unclear whether sleep problems in children with FASD stem from their direct exposure to PAE, their exposure to adversity, or both. [...]