This chapter examines wartime theories of childhood psychology, principally around the figure of the unaccompanied or orphaned child. During the war British psychoanalysts such as John Bowlby argued that wartime separation from mothers posed great psychological risks, equal if not greater to physical dangers of living in war zones. These and similar concerns shaped official policy towards state-funded day nurseries for the children of female war workers in Britain and beyond, and also informed assumptions about the psychopathologies of orphaned children in post-war Europe. The chapter also considers the smaller literature theorising the impact of fathers, living and dead, on their children during the war and in its aftermath.