Is a mother sinful if she permanently surrenders her child to his father (relinquishes custody) because of the father's refusal to care for the child during the mother's travel, his refusal for the child to travel with her, his withholding of the child's identification documents, and the child's need for vaccination?

It is permissible to relinquish custody if it does not result in harm to the child, because custody is a right of the mother and not an obligation upon her. If the father is qualified for custody and commits to it when the mother travels, he must fulfill his commitment. The welfare of the child must be paramount, so the father is not permitted to retain the child's identification documents unless there is an overriding benefit. If neglecting vaccinations harms the child, the mother must be enabled to access the necessary documents. In case of dispute, the Sharia (definition) court will decide the matter.