Is it permissible to complain about brothers who refuse to care for their elderly mother, who suffers from memory loss, or to spend on her, especially since they seized the father's inheritance, and given that the questioner's children are not pleased with the grandmother living with them?

May Allah reward you for your kindness to your mother. You should alert your children to the obligation of being dutiful to their grandmother and treating her gently. It is not permissible to expel a mother from the house, even if the house belongs to the children, due to the forbidden act of undutifulness involved, and because her maintenance becomes obligatory upon them if they abandon her. Your brothers' neglect of their mother is a forbidden act of undutifulness, and they are obligated to maintain ties with her and provide for her if they are wealthy. Advise them and bring someone who can influence them to bear upon them. Otherwise, file a complaint against them to compel them to fulfill their obligations. If they do not respond or if they are poor, then it becomes incumbent upon you or your children to provide for her.