When a person makes Du’ah for another Muslim so that Allah would forgive them, Allah accepts this Du’ah.

If your question is whether this dead person knows about this Du’ah or not, he most likely does not.

And Allah knows best

Do dua reach a dead muslim?

Supplications | March 20, 2014 7:42 pm
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I know 5 supplication of Ruku and 7 of Sujood,is it correct to Supplicate all ,or more than one?
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Is that true that every night our prophet salallahu alahi wa salam recite sura al Sajda before going to sleep?