In
Canon law, affinity is a relationship arising from the
sexual intercourse of a man and a woman, sufficient for the generation of children, whereby the man becomes related to the woman's blood-relatives and the woman to the man's.If this intercourse is between husband and wife, this relationship extends to the fourth degree of
consanguinity, and the degree of affinity coincides with that of blood relationship. Today affinity does not beget affinity. Therefore the relatives of the man do not become relatives of the woman's relatives, neither do those of the woman become relatives of the man's relatives.
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