Childhood obesity may have severe long-term consequences for health—indeed, for the overall course of a person's life. Do these harms amount to a problem of social justice? And if so, what should be done about it? Parents are usually granted considerable leeway to make decisions that affect their children's health. Social and moral theory has often overlooked the family, however, leaving us with an inadequate understanding of parental autonomy and of how social policy may influence it.