Establishment of the mahram relationship through breastfeeding
a. Breastmilk of women:
The scholars are in consensus that if a woman breastfeeds a child, he becomes her child through breastfeeding. The consensus of scholars on this ruling is transmitted by Al-Maawardee, Ibn Hazm, Ibn Abd al-Barr, al-Samarqandee, Ibn Rushd, Ibn Qudaamah, al-Nawawee, Ibn Taymiyyah, al-Zarkashee and Ibn Hajar.
b. The man to whom the breastmilk of the wife belongs [248] It is called the milk of the sire. Ibn al-Hamaam said: “The milk of the sire is from the addition of soددددething to its cause,  and “the mahram relationship is related to it” meaning: the breastmilk of the woman is produced due to her giving birth to the child of the man, be he a husband or a master,  establishes the prohibition relationship between the man and the infant because that makes him his father through breastfeeding. As a result, if the child is a female then it becomes unlawful for him to marry her because he is considered her father, nor for his brothers, because they are her paternal uncles, nor for his fathers, because they are her grandfathers, nor for his paternal uncles, because they are the paternal uncles of her father, nor for his children, even if they were not the children of the wet-nurse, because they are her paternal brothers, nor to the sons of his children because tيعhe girl is their paternal aunt). Sharh Fath al-Qadeer: (3/448). :
The four Madhabs are in consensus that the mahram relationship is established between the suckling child and the husband of the wet nurse whose conception and delivery of her husband’s child led to the production of her breastmilk. This is the view of some of the righteous predecessors.
c. Breastfeeding through the nose [249]  In Arabic, it is called Sa'aoot. or throat [250] In Arabic, it is called Al-Wajoor :
The four Madhabs are in consensus that the mahram relationship through breastfeeding is established even if the breastmilk is given through the nose or throat.
d. Mixing the breastmilk with other substances
i. Mixing the breastmilk of two or more women: The majority of scholars hold the view that the breastmilk of two or more women is mixed; the mahram relationship through breastfeeding is established for all of them, irrespective of the share of each one in the given breastmilk. This is the view of the Maliki, Shafi’i, the Hanbali Madhabs, one of the reported views of Abu Hanifah, and the view of Muhammad ibn al-Hasan and a group of scholars from the Hanafi Madhab.
ii. If the breastmilk is mixed with another liquid but prevails the liquid: The four Madhabs agree that if the breastmilk of a woman is mixed with another liquid, but her breastmilk prevails the liquid, the mahram relationship through breastfeeding is established.
iii. If the breastmilk is mixed with food but prevails the food: The majority of scholars agree that in the event where the breastmilk of a woman is mixed with food, but her breast milk prevails, the mahram relationship through breastfeeding is established, This is the view of the Maliki, Shafi’i, and Hanbali Madhabs, [251]    On condition that the characteristics of mixed breastmilk remain the same. and it is the view of Aboo Yoosuf and Muhammad Ibn al-Hasan from the Hanafi Madhab. [252]    Abu Yusuf and Muhammad ibn al-Hassan added the condition that the breastmilk being mixed with food should not be exposed to fire so it can establish the mahram relationship.
e. Milking the breastmilk in one go and giving it to the child five times, each one separately: The relationship through breastfeeding is established if the breastmilk is milked in one go [253]    Ibn ‘Abd al-Barr said: “All jurists are in consensus that the mahram relationship through breastfeeding is established due to the breastmilk that the child suckled even if the child did not suckle it directly from her breast.” [Al-Tamheed 8\257]. , then it is given to the child at five separate times. This is the view of the Hanbali and Shafi’i Madhab and the view of the Permanent Committee.
f. Suckling the breastmilk of the adulteress: The four Madhabs are in consensus that the mahram relationship through breastfeeding is established by sucking the breastmilk of the adulteress. [254] The scholars differed on whether the mahram relationship is established through breastfeeding for the adulterer.
g. Suckling the breastmilk of a virgin woman: The majority of scholars agree that suckling the breastmilk of a virgin woman establishes the mahram relationship. This is the view of the Hanafi, Maliki, and Shafi’I Madhabs and one of the reported views of Ahmad, which was chosen by Ibn Qudaamah. It is reported that the scholars are in consensus about it.

2. Breastfeeding does not qualify to establish the mahram relationship through breastfeeding:
a. Mixing the woman’s breastmilk with another substance
i. Mixing the breastmilk with liquid and the liquid prevails: The majority of scholars are in agreement that the mahram relationship through breastfeeding is not established when the breastmilk of the woman is mixed with a liquid that prevails over the milk. This is the view of the Hanafi, Maliki, and Hanbali Madhabs and the view of some of the righteous predecessors.
ii. Mixing the woman’s breastmilk with food and the food prevails: If the breastmilk of a woman is mixed with food, and the food prevails over the milk, it does not establish the mahram relationship. [255]    The Hanafi Madhab state, according to their correct view, that the breastmilk mixed with food does not establish the mahram relationship, whether the breastmilk is dominating or being dominated.   it is the view of Maliki and Hanbali Madhabs.

b. Milk Enema:
The majority of scholars hold the view that the mahram relationship through breastfeeding is not established when the breastmilk is given to the child via enemas., This is the view of the Hanafi and Hanbali Madhabs, the Shafi’i Madhab, according to its more correct opinion, and one of the views of the Maliki Madhab.
c. Breastfeeding from animal’s milk
The scholars are in consensus that the mahram relationship through breastfeeding is not established when the child suckles the animal’s milk. The consensus on that was reported by Ibn al-Munthir.
d. Suckling the breastmilk of a man
The four Madhabs are in consensus that suckling a man’s breastmilk does not establish the mahram relationship through breastfeeding., It is the view of the vast majority of all scholars.