You can make Du’ah for a deceased whenever you want as you do for yourself.

Recently my aunt passed away. How do I include her in my du’a?

Funerals | February 20, 2014 2:24 am
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When to do charity (give money etc) on behalf of a dead relative? Does this only count if its done with that dead person’s money left behind or can you use your own money and say its for the dead person?

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I want to know that I have heard,that we should not recite any ayats or soorats from quran when we go to graves, but its quite confusing because from start we use to recite soorat fatiha.