Question:
What is the Islamic ruling on milk kinship between a foster mother and a child in her care? My husband and I took a baby into our care when he was just three months and one week old. I personally breastfed him twice. Does this make him my foster (milk) son in Islam? Also, my sister breastfed him more than five times until he was fully satisfied each time. Does this create milk kinship between the child and my sister—and between him and her daughters?

Answer:
Praise be to Allah, and peace and blessings be upon His Messenger.

In Islamic law, breastfeeding (known as raḍā‘ah) carries significant legal and spiritual weight. It can establish a bond of maḥramiyyah—a non-marriageable relationship—like the one created by blood relations, provided it takes place within the first two lunar years of the child’s life.

Once a woman breastfeeds a child during this period, she becomes his foster (milk) mother. All her children—whether they were born before or after the breastfeeding—become his milk siblings. Similarly, any children breastfed by the same woman become milk siblings to each other, even if they are not biologically related.

Scholarly Opinions on Breastfeeding That Establish Maḥram Status:

• According to Imam Abu Hanifah, Imam Malik, and one narration from Imam Ahmad, any amount of breastfeeding (even once) during the valid time frame is sufficient to establish this bond.
• According to Imam Shafi‘i and the stronger view of Imam Ahmad, at least five full feedings—where the child is satisfied each time—are required to establish this relationship.

Applying This to Your Situation:

Since you breastfed the child twice during the valid age, he is considered your foster son, especially according to the Hanafi and Maliki views. Your sister, having breastfed him five or more times until he was full, also becomes his foster mother under the opinion of the majority of scholars. Therefore, your sister’s daughters are his milk sisters, and he is considered maḥram (non-marriageable) to all of you: you, your sister, and her daughters.

This milk relationship brings with it several rulings:

• He may see you, your sister, and her daughters without hijab.
• It is permissible to be in seclusion (khulwah) with him.
• Traveling together is allowed.

However, it’s important to note that certain legal rights do not transfer through milk kinship:

• He does not inherit from you or your sister.
• You are not obligated to financially support him.
• Guardianship over life or wealth does not apply.
• Zakat may still be given to him, unlike blood relatives.

And Allah ﷻ Almighty knows best.

This Fatwa is written by Dr. Hafiz Muhammad Munir Al-Azhari