Ruth 1:11
But Naomi said, "Turn back, my daughters; why will you go with me? Have I yet sons in my womb that they may become your husbands?
Genesis 38:11
Then Judah said to Tamar his daughter-in-law, "Remain 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 in her father's house.
Deuteronomy 25:5
"If 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 husband's brother shall go in to her and take her as his wife and perform the duty of a husband's brother to her.