Several psychological instruments have been developed and used over the years to measure various domains of child development. The Australian Early Development Index (AEDI) is a current assessment tool being used as a community measure of young children's development. It measures the following domains: Physical health and wellbeing; Social competence; Emotional maturity; Language and cognitive skills; Communication skills and general knowledge. This article examines the tacit nuanced construction of the child within the AEDI, and critiques this within a cultural-historical theoretical perspective of child development. The paper argues that the AEDI image of the child has its roots in Piagetian and Gesellian stage theories of universality. This position is juxtaposed with more encompassing views held in the Vygotskian tradition. The paper advances arguments for an alternative consideration of child development that does not prescribe vulnerability to certain groups of children.