Praise be to Allaah.
The breastfeeding by which the relationship of mahram is
achieved is subject to two conditions:
1 – That there should have been five or more feedings
2 – That it should have taken place within the first two
years of life, before weaning.
See the answer to question no.
40226 for more information on these
It is not stipulated that the child should have drunk his
fill of milk, rather taking in the nipple and sucking milk is regarded as
If the child takes in the nipple but no milk comes out, that
is not breastfeeding, and does not mean anything.
It says in al-Fataawa al-Hindiyyah (1/104): Because
when the milk comes out, breastfeeding takes place, otherwise it does not.
In Fataawa al-Lajnah al-Daa’imah (21/53) it says: If
your mother gave the breast to your paternal uncle to keep him quiet, and he
did not receive any milk from her breast, then there is no relationship of
mahram, and the marriage is permissible. End quote.
If there is any doubt as to the number of breastfeedings, or
whether breastfeeding took place, then the relationship of mahram cannot be
The scholars of the Standing Committee were asked:
I have a female cousin (the daughter of my maternal aunt) and
I want to marry her, but the problem is that that there is some doubt
concerning our relationship through breastfeeding, as breastfeeding was
shared between my grandmother (the mother of my mother) and her mother. But
this grandmother is not sure about this breastfeeding. We asked her and she
said, “I don’t know, I have forgotten. If this girl breastfed from me, there
was no milk then.” This is what the grandmother says. I hope that you can
find a proper solution for me; is marriage to her permissible or not, based
on what the grandmother says?
If the situation is as
described, then you may marry the cousin whom you mentioned, because
breastfeeding concerning which there is some doubt does not have any effect.
Rather the relationship of mahram through breastfeeding is only established
if there were five or more breastfeedings, during the first two years of
life. If it is not known, then the basic principle is that this marriage is
permissible. End quote.
Fataawa al-Lajnah al-Daa’imah,
See also question no. 804
Based on this, your brother who it is proven breastfed from
your maternal aunt is a son to her through breastfeeding, and is a brother
to all her children.
But in your case there is no proof that the relationship of
mahram was established because there is some doubt and hesitation with
regard to breastfeeding.
And Allaah knows best.