'Father in law' in the Bible

Now his daughter-in-law, Phinehas’s wife, was pregnant and about to give birth; and when she heard the news that the ark of God was taken and that her father-in-law and her husband had died, she kneeled down and gave birth, for her pains came upon her.

And she called the boy Ichabod, saying, “The glory has departed from Israel,” because the ark of God was taken and because of her father-in-law and her husband.