The whole human race was condemned in its apostate head (Adam) by a divine judgment so just that even if not a single member of the race were ever saved from it, no one could rail against God's justice.

But what about those who never commit any offense against God at all, such as those who die in infancy or those who, because of severe brain damage or some other factor, never develop into minimally rational agents? These too, according to Augustine, deserve to be condemned along with the human race as a whole. “For … the whole human race,” he insisted, “was condemned in its apostate head by a divine judgment so just that even if not a single member of the race [including, therefore, those who die in infancy] were ever saved from it, no one could rail against God’s justice” (Enchiridion, 99)....