Can a father's prayer against his daughter be answered when he prays for her death, or with other prayers that do not please Allah, due to her inability to intervene in the matter of his separation from his wife?

A parent's supplication against their child, if made unjustly, will not be answered. It is only answered if the child has committed an act of disobedience that makes him or her a wrongdoer towards the parent. Scholars have differed on the entitlement to the custody of a girl after the age of seven, whether it belongs to the father or the mother, or if she should be given a choice. Therefore, there is no sin upon the girl if she stays with her mother, especially if staying with her father would expose her to harm. However, she must fulfill her duty of righteousness towards her father and not mistreat him. If she is righteous towards him, his supplication against her will not harm her.