Deuteronomy 21:15

If a man has two wives, the one loved and the other unloved, and both the loved and the unloved have borne him children, and if the firstborn son belongs to the unloved,

If a man has two wives, the one beloved, and the other hated, and they have borne him children, both the beloved and the hated; and if the firstborn son is hers who was hated;