This article is the first indepth ethical analysis of empirical studies that support the claim that children born without major parts of their cerebral cortex are capable of conscious experiences and have a rudimentary capacity for agency. Congenitally decorticate children have commonly been classified as persistently vegetative, with serious consequences for their well-being and opportunities to flourish. The paper begins with an explication of the rights-based normative framework of the argument, including conceptual analysis of the terms ‘agency’, ‘potentiality for agency’ and ‘gradual approach of agency’. It critically examines Alan Gewirth’s account of the criteria for being a rights bearer and principles for settling rights conflicts between agents and potential agents. It then applies the rights-based normative framework to the ethical challenges associated with care for congenitally decorticate children. It argues that recent empirical studies support the claim that the concepts ‘potential for agency’ and ‘capacity for rudimentary agency’ apply to children who are born without major parts of their cerebral cortex. The article finally discusses important medical ethical implications of these results. It specifically focuses on congenitally decorticate children’s preparatory rights to a stimulating intellectual and social environment.