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Levirate marriage is the obligation of a surviving
brother to marry the widow of his brother if he died without having sired
children. The outcome is that the widow must marry a brother-in-law rather than
anyone outside the family. The oldest of the surviving brothers had the first
obligation to perform this commandment, which also allowed him to inherit all
of his dead brother’s property.
Sororate marriage is
the sociological custom of a man marrying or engaging in sexual activity with
his wife's sister, usually after the wife is dead or has proven infertile. From
an anthropological standpoint, this type of marriage strengthens the ties
between both the wife's family or clan and the husband's and preserves the
contract between the two to provide children and continue the alliance.
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