Duas for an immature deceased
In the name of Allah, the most Beneficent, the most Merciful.
The following dua should be recited for your niece who has sadly passed away. “O’ Allah! Make him a source of happiness for us, and make him a reward and a treasure for us, and make him for us an intercessor and an accepted intercession.” (Kitabul Janaiz p.31)
Duas on the line of making the child a source of happiness and an intercessor for the parents should be made. I will conclude by mentioning a couple of ahadith from Imam Bukhari’s Al Adabul Mufrad (p.55)
Saaiduna Abu Hurairah Radiallahu Anhu narrates that a woman came to the Prophet of Allah Sallallahu Alahi Wasalam with a child. She said, "Make supplication for him. I have buried three children." He said, "You have built a strong barrier against the Fire."
Saaiduna Jabir Ibn Abdullah Radiallahu Anhu narrates "I heard the Prophet of Allah Sallallahu Alahi Wasalam say, 'If anyone has three of his children die young and resigns them to Allah, he will enter the Garden.' We said, 'Prophet of Allah, what about two?' 'And two', he said." Mahmud Ibn Labid said to Jabir Radiallahu Anhu "By Allah, I think that if you had asked, 'And one?' he would have given a similar answer." He said, "By Allah, I think so too."
Only Allah Knows Best
Mohammed Tosir Miah
Darul Ifta Birmingham.