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The brother-in-law (husband of the sister) is also a “non-mahram” and veil is required in front of him, according to the Shari’ah guidelines. Especially when he asks to remove the hijab or objects to it, it becomes even more dangerous situation. Additional protection should be exercised from such people. Usually where there is no veiling culture within a household between the sister-in-law and other relatives, there are sure to be erroneous temptations. 

Instead of placing a veil on the face, cover your entire body with an outer garment (large sheet of cloth), which covers the face and the entire body. It is not necessary to wear a special veil on the face permanently. Also, don't talk to him unnecessarily. If there is an important matter to speak about, then use firm tone, without creating flexibility and softness in speech, stay in the veil and speak only as much as is necessary, and avoid frankness and humor at all costs.

If it is possible to move to another house, then the location should be changed, but if this is not possible, then stay in a separate room as long as practically possible. 

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