Will you explain the terms milk kinship and milk bank?

- Are children of a wet nurse and the children she breastfed mahram? Is it permissible for them to get married?

Dear Brother / Sister,

Milk kinship is one of the drawbacks to marriage peculiar to Islamic law. This prohibition was introduced by verse 23 of the chapter of an-Nisa. In this verse, God Almighty prohibited the believing men from marrying their wet nurses and milk sisters. The following is stated in a hadith:

"What is haram through birth is haram through breastfeeding." (Muslim, Rada: 1)

One of the biggest wisdoms of this prohibition is that the milk of human beings, who are the most honorable beings, is also very valuable and that a different bond of kinship is established among human beings through breastfeeding. Milk establishes a material connection and a spiritual connection that is impossible to eliminate between the mother and the child. Milk kinship is a different means of solidarity and an independent element of approaching for people. Therefore, milk relatives are regarded as mahram and it is forbidden to marry them. They can look at one another but they cannot marry.

It is necessary to be very careful about whether there is a milk kinship between the people who will get married. For milk kinship prevents marriage. According to Abu Hanifa, a woman who breastfeeds or gives milk to a child at most two and a half years (30 months) after birth - according to Imam Muhammad and Imam Abu Yusuf, two years - is regarded a wet nurse. With this breastfeeding, kinship occurs between the child and the wet nurse and the mahram relatives of the wet nurse and the other children who were breastfed by the same wet nurse. It is enough for a little amount of milk to go down the stomach for kinship. 

It is not necessary to suck the milk from the breast. It is enough for the milk to be sent to the stomach through other ways. According to Shafiis and Hanbalis, kinship through breastfeeding does not occur when a baby is breastfed once; it is necessary to be breastfed at least five times by the same mother.

The milk of a woman that is drunk or sucked by a child after he is two and a half years old does not bring about kinship through milk. That is, when a boy who is two and a half years old or older is breastfed by a woman, she does not become his wet nurse.

The women that a man cannot marry due to kinship through milk are as follows:

1. Wet nurse: He cannot marry the mothers (both milk and biological) of the wet nurse and her husband. Accordingly, a person cannot marry her wet nurse first of all. He cannot marry the biological or milk mother of his wet nurse. The same prohibition is valid for her husband's biological mother or wet nurse or grandmother.  

2. The girls that his wife breastfed: He cannot marry the biological and milk daughters of his milk daughter. A man cannot marry the girls that his wife breastfed because they are like his own milk daughters. Similarly, it is forbidden for him to marry the biological or milk daughters of his milk daughters and sons, that is, his milk granddaughters. This line called "furu" goes on in chain and the grandfather cannot marry his milk granddaughters.

3. His full or maternal/paternal half sisters of milk kinship: He cannot marry the biological and milk daughters of his milk brothers and sisters and their daughters. A man cannot marry his milk sisters, either. The children who sucked milk from the same wet nurse are milk sisters or brothers. The biological and milk children of a woman who breastfeeds other children and her husband's children are full milk sisters and brothers. The biological and milk children of a woman who breastfeeds other children from her previous or future husband are maternal half milk sisters or brothers. The biological and milk children of a husband from another wife are paternal half milk sisters or brothers with the children of his wife who breastfeeds. A man cannot marry any of these milk sisters.

4. His full or maternal/paternal half maternal and paternal aunts: He cannot marry his biological mother and father's milk mothers, milk sisters milk maternal and paternal aunts. In that case, the biological and milk brothers and sisters of the milk father and the biological and milk brothers and sisters of the milk mother are milk relatives of the children who suck milk. Therefore, a man who sucks milk cannot marry milk maternal and paternal aunts. The relatives of the milk mother and milk father are the relatives of the milk son but the relatives of the milk son except his wife and children are not relatives of the milk mother and milk father. For instance, a milk mother can marry the biological father or brother of her milk son.

It is necessary to say that the following statement that is widespread among people about milk kinship is not a statement based on the Shari'ah: "Milk kinship does not go down; it goes up." The children who suck from the same breasts are milk siblings even if they suck at different time periods and even if their fathers are different as long as they suck within the age of breastfeeding. Therefore, a wet nurse's son cannot marry a girl who was breastfed by his mother; his son cannot marry her either. It does not matter whether her son was born before or after the girl sucked milk from her and whether there were many years between the child's birth and her breastfeeding.

Click here for information about milk bank:

Is it permissible to establish a milk bank? What are the disadvantages of it and what measures can be taken against them?

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