Cross reference
Ruth 1:11
11 Naomi said, Turn again, my daughters: why will you go with me? have I yet sons in my womb, that they may be your husbands?
Deuteronomy 25:5
5 If brothers dwell together, and one of them die, and have no son, the wife of the dead shall not be married outside to a stranger: her husband's brother shall go in to her, and take her to him as wife, and perform the duty of a husband's brother to her.
Genesis 38:11
11 Then Judah said to Tamar, his daughter-in-law, "Remain a widow in your father's house, until Shelah, my son, is grown up;" for he said, "Lest he also die, like his brothers." Tamar went and lived in her father's house.