Is it permissible for the brother’s wife to unveil her face in front of her husband’s brother, whom her sister raised, and what is the ruling on this brother honoring his father’s wife who raised him?

The marriage of a brother to his father's wife's sister is permissible, because she is not among the forbidden women. As for the brother's wife, it is not permissible for her to uncover any part of her body to the husband's younger brother, because he is a stranger to her, and the fact that she raised him when he was young does not make him a mahram to her. The brother must honor his birth mother. As for his father's wife who raised him, she is not his mother in the sight of Islamic law, but it is proper to treat her kindly and benevolently, and his saying to her "O my mother" is permissible as a form of honor and affection.