Is it permissible for a Muslim to enter - without asking permission - to the room of his veiled sisters-in-law, since he is their temporary Mahram (unmarriageable relative)?
A: A husband is not a Mahram of his wife's sisters. Thus, it is not permissible for him to be alone with them and it is not permissible for them to expose any of their physical beauty to him. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.