Therefore...

Therefore, the elder brother does not have the right to hit the younger brother unless he is the legal guardian of the child or authorized by the guardian. It is not permissible at all to hit a school pupil without the permission of his guardians or someone authorized by the guardian.

(See the question-answer section below.) It is not permissible to hit a baligh child in order to prevent him from an evil act, except in accordance with the conditions of al-amru bi ’l-ma‘rûf wa ’n-nahi ‘ani ’l-munkar (enjoining the good and forbidding the evil) with the permission of the religious authority. Based…