The advancement of inclusive education policies worldwide has given greater weight to social justice practices in educational settings. However, inclusion in preschools has received less attention from researchers. This article examines a 4-year-old child's participation in a mainstream preschool in Australia from a cultural-historical perspective. In particular, this study used the concept of secondary disability to analyse the data, and in this process identified a contradiction between the teacher's perceptions of the child's abilities and the teacher's reported understanding of the parent's perceptions of the child's abilities, which 'clouded' the child's position within the preschool setting. Eight hours of video data were gathered across eight months. The findings indicate that understanding the child's personality and potential can operate as a 'pedagogical password' for the teacher to enter on to the child's unique developmental trajectory. This paper argues that identifying the unique developmental pathway of the child is essential to reduce secondary disabilities.