Esal-e-Sawab or Sadqa-i-Jaria is not an absolute thing, it is subject to the person’s intentions (for whom it is being done) and their efforts when they were alive in this world. If the intention was there before the person passed away, then doing of such an act on their behalf will Insha’Allah reap additional rewards for the dead. Had there been no intention or effort to begin with, then as a principle, there cannot be any reward for the dead. In the latter case, the reward will go to the person performing that deed.

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For comments of Ghamidi Sahab, please refer to the video below from 39:51 to 42:37

https://youtu.be/v83PFzLI29U?t=2391