This article explores the enduring influence of eugenic ideas on British psychiatry and social policy in the aftermath of the Second World War, with a specific focus on the establishment of children reception centres. It provides a detailed case study of the Caldecott Community in Kent, and its involvement in the creation of an experimental reception centre, alongside members of the British Eugenics Society, notably the psychiatrists Hilda Lewis and Carlos Blacker. It demonstrates how these psychiatrists attempted to forge a link between childhood behavioural development and adult neuroses based upon environmental influences, such as adverse home conditions, coupled with assumptions about the hereditary susceptibility of behaviours and abilities linked to the causes of poverty. It explores how eugenic ideas influenced the categorisation of ‘problem families’ during the experiment, the collection of family and social background history on the children sent to the reception centre, and how hereditarian ideas influenced the eventual separation of children from their parents. The article demonstrates how eugenics, via a pathologisation of childhood and family life, was able to integrate into the policy debates on child welfare within early post-war Britain.