The mahram relationship is not established if there is any doubt about the number of breastfeedings

Dear Brothers & Sisters,
As-Salaamu-Alaikum wa Rahmatullahi wa Barakatuh. (May Allah's Peace, Mercy and Blessings be upon all of you)
One of our brothers/sisters has asked this question:

My stepmother breastfed the son of my full brother but she is not sure about the number of times she breastfed him, and she is not sure whether this breastfeeding establishes the mahram relationship or not, because this nephew wants to propose to my daughter.
Please advise us, may Allah reward you with good.

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Check below answers in case you are looking for other related questions:
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He was breastfed with her maternal uncle five times – is she forbidden for him for marriage?

Answer:

Praise be to Allah

As there is some doubt about the matter, and you do not know whether it was five breastfeedings or four, or less than that, then the basic principle is that the mahram relationship does not exist. As that is the case, there is nothing wrong with this marriage, and this breastfeeding concerning which there is some doubt is not considered to establish the mahram relationship.

And Allah knows best.

Whatever written of Truth and benefit is only due to Allah's Assistance and Guidance, and whatever of error is of me. Allah Alone Knows Best and He is the Only Source of Strength.
Your brother and well wisher in Islam

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