Jesus said, Suffer little children, and forbid them not, to come unto me: for of such is the kingdom of heaven. Matthew 19:14

Take heed that ye despise not one of these little ones; for I say unto you, That in heaven their angels do always behold the face of my Father which is in heaven. Matthew 18:10

Do not remove your hand from your son or daughter; rather, teach them the fear of God from their youth. Didache (A.D. 80-140) ch. 4

Let our children be partakers of the instruction which is in Christ: let them learn how lowliness of mind prevails with God, what power chaste love has with God, how the fear of Him is good and great and saves all them that walk therein in a pure mind with holiness. For He is the searcher out of the intents and desires; whose breath is in us, and when He lists, He shall take it away. Clement of Rome (A.D. 96) ch.21

Yet it is not for this that God is wroth with you, but that you may convert your family, that has done wrong against the Lord and against you their parents. But out of fondness for your children you didst not admonish your family, but didst suffer it to become fearfully corrupt. Hermas (A.D. 150) ch.10

Only be not you careless, but take courage, and strengthen your family. For as the smith hammering his work conquers the task which he wills, so also does righteous discourse repeated daily conquer all evil. Cease not therefore to reprove your children; for I know that if they shall repent with all their heart, they shall be written in the books of life with the saints. Hermas (A.D. 150) ch. 10

"But do you, Hermas, no longer bear a grudge against your children, neither suffer your sister to have her way, so that they may be purified from their former sins. For they shall be chastised with a righteous chastisement, unless you bear a grudge against them yourself." Hermas (A.D. 150) Ante-Nicene Fathers vol.2 pg.11

And for the married he goes on to say, "My elect shall not labor in vain nor bear children to be accursed; for they are a seed blessed by the Lord." For him who begets children and brings them up and educates them in the Lord, just as for him who begets children by means of the true teaching, a reward is laid up, as also for the elect seed. Clement of Alexandria (A.D. 195) Miscellanies, book III ch. 15