In France, definitions of childhood and relations between adults (parents, professionals, public authorities, scientists, even sociologists ...) and children, continue to be matters of debate in everyday life, scientific practices and political arenas. This article intends to show how these debates can be analysed as an object of research, using Boltanski’s sociological model of Justification. The presentation of this framework highlights its relations to the contributions of two other French sociologists whose works are not directly interested in childhood: Bourdieu and Latour. It is centred on two main aspects of this model: the study of operations of critiques and justifications based on a pragmatic sociology of critique and the idea of its double requirement: equality and order between human beings. It shows how this framework can be useful for thinking about childhood–adulthood relations as a moral and political order which is an object of debates. Then, from an historical example, the author proposes a short case study of what may be called an analysis of the moral sense of justice towards children.