This paper provides a discourse analysis of 12 Swedish sexuality education texts intended for preschool practitioners and published between 1969 and 2021. Using Fairclough's framework, we identify three discourses about children's sexual play in relation to children's sexual agency in the texts: child sexuality as encouraged and entangled with adult sexuality; child sexuality as conditioned by what is perceived as normal or abnormal in children; and child sexuality as repressed. These three discourses mainly appear chronologically, but also overlap and connect with one another. When analysis begins from children's position and a theoretical understanding of children's and adults' agency as interdependent, it becomes possible to see how the child is construed as agentic, and how the adult role changes from encouraging sexual play to regulating and monitoring behaviour so that it does not occur. Over time, discourse on young children's sexual play has changed our understanding of both adults and children. Adults are increasingly construed as less knowledgeable in relation to young children's sexuality, and young children have become understood as more dangerous and in need of having their sexuality constrained and civilised.