Woman's brother-in-law is not a Mahram to her
12-5-2009 | IslamWeb
Question:
salam. my eldest sister died in earth quake in 2005. at that time her son was 5 years old. at that time of grief my brother in law(B-I-L, my dead sister's husband) stayed at our home for a year time because of his son. our nephew is very close to my younger sister, so my B-I-L decided to keep him with us, secondly his own house was all destroyed in earth quake and his parents live in quite far away city. at that time, me, my nephew and my B-I-L use to go in same car, as v drop nephew to school while me and my B-I-L were working in same hospital. because my B-I -L stayed at our home and drop me to my hospital, my Fiance got very annoyed and he used very abusive language for my parents and B-I-L. that time i thought its just coz of his fear that my parents might marry me to my B-I-L, i beared all wat he said, even though it was v v hurtful. for the last three years i married, but my husband keeps accusing my parents for leting my B-I-L stay and to drop me to work. i was always fully covered in front of my B-I-L, i wear scarf wen i go out but ya i did talk to my B-I-L like a sister talks to her brother, v talked about my died sister and things like that. i just wana ask, if me, my parents my B-I-L were wrong in light of Islam, then r v answerable to ALLAH or to my husband? does my husband who was my fiance (engegment not a islamic relation) at that time he has any right to blame or scold us and then to behave in a rude manner with my parents? if my B-I-L became na mahram after my sis death, then if i wld hv gone to hospital in sm public transport then again, all those wld also be na mahram for me? if my B-I-L stayed with us in that time of extreme pain for his child, wats so wrong in it? so r v guilty for our actions, if yes, then to whom? v need to ask for forgiveness to ALLAH or my husband?for past two years my B-I-L himself got married sm1, he just visits my parents home once a month to meet his son. PLEASE give me a detailed answer, this issue has ruined my life
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
First of all, please accept our condolences on the death of your sister and we ask Allaah to forgive her and bless her son.
As regards the husband of your sister coming to your home, then this is permissible if this does not lead to evil, like him entering the house in an impermissible manner or staying in seclusion with whom he is not permitted to stay in seclusion with. Moreover, your fiancé has no right to get angry because of this or blame anyone of you about it, let alone speaking to your parents in a harsh manner or blaming them about it.
As regards you riding in a car alone with the husband of your sister, then this is not permissible because he is a non-Mahram to you and being in seclusion with him in a car is considered a forbidden seclusion, or in the meaning of a forbidden seclusion.
However, if your parents agreed with you about this while knowing that it is forbidden, then they are to be blamed as well. Therefore, all of you should repent to Allaah. For more benefit, please refer to Fataawa 88013 and 83362. It should be mentioned here that the husband of the sister is not a Mahram even if the sister was still alive and they were still married, because being a Mahram to someone is confirmed with the permanent prohibition from marrying him/her and not the temporary prohibition, like the prohibition of having two sisters as wives at the same time; for more benefit, please refer to Fatwa 84623.
As regards the fiancé criticizing you for that matter, then this is permissible because this is included in enjoining good and forbidding evil, and for this, it is not necessary that there should be a legitimate relationship between both of you. However, since what happened already took place, then your husband should not create some kind of tension because of what had already happened, but he should forget the past and continue the marital life, as Islam guides us to follow an important rule as Allaah Says (what means): {… either keep [her] in an acceptable manner or release [her] with good treatment.}[Quran 2:228]
Allaah Knows best.