06/05/16 AFFINITY & CONSANGUINITY
The former refers to relationship by marriage, the latter to relationship by blood. The distinction is usually carefully observed in legal writing. E.g., “The statutes prescribe the classes of persons entitled to appointment as administrator and indicate an order of precedence based on kinship by consanguinity or affinity with the decedent.”
Affinity takes the preposition between or with, not to or for.