The extent of hijab from a mahram
Question
To what extent should a woman who observes hijab keep hijab from her sister’s husband, her brother, her paternal aunt’s husband, her paternal uncle and her husband’s younger brother; that is, what is its degree in the Shari‘a? And is there any harm if she comes before them with her face uncovered and her hands uncovered only up to the wrists? That is, to what degree is hijab required from these people?
Answer
There is no hijab from the brother and the paternal uncle; from the sister’s husband, the paternal aunt’s husband, the paternal cousin and the like there is hijab — she should not come before them at all. If they live in one house and the house is cramped, then out of necessity even this much hijab suffices: she should not uncover her face and hands, but rather draw a veil…
Source: Fatawa Mahmudiyya
Preview. The full text opens with JavaScript enabled.