Ruth 1:11
And Naomi said, "Return, my daughters. {Why do you still want to go with me}? [Are there] sons {in my womb} that may be husbands for you?
Genesis 38:11
Then Judah said to Tamar, his daughter-in-law, "Stay a widow in your father's house until Shelah my son grows up," for {he feared he would also die} like his brother. So Tamar went and stayed in the house of her father.
Deuteronomy 25:5
"When brothers dwell together and one of them dies and has no son, the wife of the deceased shall not become the wife of a {man of another family}; her brother-in-law {shall have sex with her}, and he shall take her {to himself} as wife, and he shall perform his duty as brother-in-law [with respect to] her.