Catechism of the Catholic Church §2221 — excerpt
The fecundity of conjugal love cannot be reduced solely to the procreation of children, but must extend to their moral education and their spiritual formation.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: GE 3 · FC 36