This paper explores some of the ethical issues around offering COVID-19 vaccines to children. My main conclusion is rather paradoxical: the younger we go, the stronger the grounds for justified parental hesitancy and, as such, the stronger the arguments for enforcing vaccination. I suggest that this is not the reductio ad absurdum it appears, but does point to difficult questions about the nature of parental authority in vaccination cases. The first section sketches the disagreement over vaccinating teenagers, arguing that the UK policy was permissible. The second section outlines a problem for this policy, that it faces justified vaccine hesitancy. The third section discusses three strategies for responding to this problem, arguing that there may be no simple way of overcoming parents’ reasons to resist vaccinations.