עֶרְוַ֥ת אֵֽשֶׁת־אָחִ֖יךָ לֹ֣א תְגַלֵּ֑ה עֶרְוַ֥ת אָחִ֖יךָ הִֽוא׃ (ס)
Targum Jonathan on Leviticus
The nakedness of thy brother's wife thou shalt not dishonour in the life-time of thy brother, or after his death, if he have children; for it is the nakedness of thy brother.