Is it permissible for a mother to take her children with her after divorcing their father, who is mentally ill and has caused psychological distress to his young children?

Obsessive whisperings (Waswas) are an evil and a great misfortune, originating from the devil's plot. One must be diligent in thwarting the devil's aims, seeking Allah's help, and enlisting the aid of all who can assist in reconciliation and advising the father. If a divorce occurs, custody belongs to the mother unless she remarries, whereupon custody transfers to the one most deserving, while prioritizing the well-being of the child. Should a dispute arise, the Sharia court will adjudicate it.