Catechism of the Catholic Church

2201 The conjugal community is established upon the consent of the spouses. Marriage and the family are ordered to the good of the spouses and to the procreation and education of children. The love of the spouses and the begetting of children create among members of the same family personal relationships and primordial responsibilities.

2202 A man and a woman united in marriage, together with their children, form a family. This institution is prior to any recognition by public authority, which has an obligation to recognize it. It should be considered the normal reference point by which the different forms of family relationship are to be evaluated.

2203 In creating man and woman, God instituted the human family and endowed it with its fundamental constitution. Its members are persons equal in dignity. For the common good of its members and of society, the family necessarily has manifold responsibilities, rights, and duties.