Is it sufficient to recite Surat Al-Mulk once with the intention that the reward be for the reciter and all members of his family, or is it obligatory to recite it according to the number of family members for the intention to include them?

It has been previously stated that Surat Al-Mulk intercedes from the torment of the grave, and this is not merely by reciting it, but by believing in what it contains and acting upon its rulings. Reciting it once for oneself is sufficient. However, regarding reciting it on behalf of others, especially living individuals who have not adhered to it, there is a difference of opinion among scholars. The more evident view is that this should not be done, due to the absence of any narration from the Prophet (peace be upon him) and his companions concerning it, as acts of worship are prescriptive (tawqifiyyah). The more cautious approach is not to recite it for anyone, whether living or dead.