What is the ruling of Islamic law on dealing with a sister who incites her mother against her children and their wives, and causes discord in the family? Is it permissible for the children to avoid their mother because of this? And what should the siblings do regarding this sister, and is it permissible to cut ties with her?

What has been mentioned about the mother and her daughters—namely, ill-treatment, incitement, lying, insults, and backbiting—is a grave mistake and impermissible. However, it is not permissible for children to sever ties with their mother or sisters, due to the great right the mother possesses and the obligation to honor her and maintain kinship ties. Children can avoid mistreatment when visiting the mother.