Evidence indicates that Sickle Cell Disease (SCD) threatens neurodevelopmental outcome. Although children with SCD may be heterogeneously affected, neurocognitive impairment may already be present in toddlers. Neurocognitive functioning is an important determinant of adaptive daily life functioning later in life and is influenced by both the course of the disease and the often suboptimal environment in which afflicted children grow up. Early identification of children at the highest risk of neurocognitive impairment would enable the deployment of early interventions to mitigate the detrimental effects of SCD on the developing brain. In order to develop such interventions, a deeper understanding of the underlying pathophysiological mechanisms is required. Therefore the main aim is to study early neurocognitive functioning and development in children with SCD between the ages of 6 and 24 months old.