Born with a fallen human nature and tainted by original sin, children also have need of the new birth in Baptism to be freed from the power of darkness and brought into the realm of the freedom of the children of God, to which all men are called. The sheer gratuitousness of the grace of salvation is particularly manifest in infant baptism. The Church and the parents would deny a child the priceless grace of becoming a child of God were they not to confer Baptism shortly after birth (CCC 1250).
Original sin is a reality from which each and every human person desperately needs to be freed. Biblically speaking, Romans 5:12 is remarkably clear on this point:
Therefore as sin came into the world through one man and death through sin, and so death spread to all men because all men sinned.