Is it permissible for a sister, in her capacity as an heir residing in her deceased parents' house, to open her brother's locked, unused room and utilize it for her and her children's dwelling due to the cramped conditions of her current residence?

Ownership of an inherited house transfers to all heirs according to their respective shares. The mere presence of the questioner alone in the house does not entitle him to utilize the entire property without the permission of the other heirs. If the property is divisible, it should be divided; otherwise, it should be divided through a usufructuary partition (muhayah) or a mutually agreeable partition (muradah), or it should be sold and its price distributed. If the heirs are the questioner and his brother, and each has a room, the questioner is not permitted to open his brother's room and benefit from it without his permission, unless with the brother's cheerful consent.