'Brother in law' in the Bible

So Judah instructed Onan, "You are to have sexual relations with your dead brother's wife, performing the duty of a brother-in-law with her, and have offspring for your brother."

"When two brothers are living together and one of them dies without leaving a son, his widow must not be married outside the family to a foreigner. Instead, the brother-in-law must go to her, take her as his wife, and by doing so perform the duty of a brother-in-law.

But if the man does not want to marry his brother's widow, then she must go to the elders at the city gate and declare, "My husband's brother refuses to perform the duty of a brother-in-law in order to preserve the name of his brother in Israel. He is not willing to perform the duty of a brother-in-law.'

then she is to approach her brother-in-law in the presence of the elders, remove his sandal, spit in his face, and say in response, "May this be done to the man who does not preserve the lineage of his brother.'

And the children of the Kenite, Moses brother-in-law, went up out of the city of palm-trees with the children of Judah into the wilderness of Judah, which is in the south of Arad; and they went and dwelt with the people.

Now Heber the Kenite had separated himself from the Kenites, even from the children of Hobab the brother-in-law of Moses, and had pitched his tent as far as the oak in Zaanannim, which is by Kedesh.

Now in the fifth year of King Rehoboam, Shishak king of Egypt [Jeroboam’s brother-in-law] came up against Jerusalem.