❖ Source:
Fatāwā Amunpuri by Shaykh Ghulam Mustafa Zaheer Amunpuri
❖ Question:
One of my wives breastfed a girl. Can that girl’s daughter marry the son of my other wife?
✿ Answer:
No, this marriage is not permissible.
The girl who was breastfed by your wife becomes a milk-daughter to your wife and a milk-stepdaughter within your household.
Her daughter, in turn, becomes a milk-niece (raḍāʿī bhānjī) to your other wife’s son (your stepson).
Thus, the two — the girl’s daughter and your other wife’s son — are regarded as milk maternal uncle and niece (raḍāʿī māmu-bhānjī) to each other.
Just as marriage between a biological maternal uncle and niece is prohibited, likewise, marriage between a milk maternal uncle and niece is also forbidden, due to the general ruling:
“Whatever relationship is prohibited by birth (nasab) is also prohibited through breastfeeding (raḍāʿah).”
❖ Quranic Evidence:
وَبَنَاتُ الْأُخْتِ
﴿النساء: 23﴾
Translation:
“And the daughters of your sisters (are also forbidden to you in marriage).”
[Surah An-Nisā’: 23]
This includes both biological and milk-nieces.
Summary:
- One wife breastfed a girl → that girl becomes her milk-daughter.
- Her daughter becomes milk-niece to the son of the co-wife.
- Marriage between a raḍāʿī maternal uncle and niece is impermissible.