I had brother who passed away and I had some deals with him, he used to live with my mum and sister, he was married and has one kid, we agreed to buy the house where they were living in using my sister, my mother and my money, as well he added some of his own money to get the amount for the house, but he had the house registered on his name and mine, knowing that his share was, let say 10% percent, our share (my self, my sister and my mum) was 90% percent, so now his wife is claiming her share of the house according to the legal paper which is 50% percent and she knows about our shares but she doesn't want to do it according to the correct share so she wants to divide it according to the paper which has only my name and my brother's name (passed away), on the other hand he had a small business on my name which has the value roughly the same value as the house shares lost in the argument (my sister and my mum), this business is registered legally on my name but I don't have any shares from it, it is 100% percent my brother's. Do I have the right to keep the business as the lost shares or do I have to hand it back to his widow and son?

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.

You are obliged to remind the widow of your deceased brother of Allaah and warn her against taking people's property without legal right because she knows that the house -as you said in the question -is a shared property (between her deceased husband and his brothers).

In case she does not accept your advice and insists on taking the right of your brothers by law, then you are permitted to only take the similar amount that is seized by her, from her husband's business in order to compensate your brothers who had lost their share in that house. If any money remains after paying the rights, then you have to return it to your brother's wife and his children.

However, some scholars are of the view that it is forbidden to do so as the Prophet said: "Give back the trust to whoever has entrusted you with it, and do not cheat whoever has cheated you." [Abu Daawood and At-Tirmithi]

Nonetheless, the preponderant opinion is that if a Muslim can take his right back, then it is permissible for him to take it as the Prophet said to Hind Bint 'Utbah [when she inquired about what she could take from her husband's property without his consent or permission]: "Take what is reasonable and sufficient for you and your children." [Al-Bukhari and Muslim]

Allaah Knows best.