Genesis 38:11

11Then Judah said to Tamar his daughter-in-law, aRemain a widow in your father’s house, till Shelah my son grows up”—for he feared that he would die, like his brothers. So Tamar went and remained bin her father’s house.

Deuteronomy 25:5

Laws Concerning Levirate Marriage

5 cIf brothers dwell together, and one of them dies and has no son, the wife of the dead man shall not be married outside the family to a stranger. Her dhusband’s brother shall go in to her and take her as his wife and perform the duty of a husband’s brother to her.
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