'Father in law' in the Bible

His daughter-in-law, Phinehas' wife, was with child, near to be delivered. When she heard the news that the ark of God was taken, and that her father-in-law and her husband were dead, she bowed herself and brought forth; for her pains came on her.

She named the child 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.