What is the Sharīʿah's view on some heirs demanding their share of the commercial shop left by their father? Is it permissible to discuss inheritance while their mother is still alive? Do they have a share in the income of the sister who works in the shop and spends from it on the household and their mother?

Whatever wealth or possessions the deceased leaves behind belong to all the heirs. They may sell what was left and divide the price among themselves, each according to their share, and this is the safest solution. Otherwise, they may keep the machinery and the shop if they agree to do so, and the working sister can rent it, or work in it on a Mudarabah basis with a percentage of the profit. The mother's continued life does not prevent the division of inheritance if one of the heirs requests their share. If her share is not sufficient to meet her needs, then her maintenance is obligatory upon the wealthy among her children, and if they are equal, it is distributed among them.