The Prohibition of Marrying the Daughters of a Breastfeeding Mother

Question:
One of the listeners sent a question saying: I was breastfed by my cousin’s mother, and he was breastfed by my mother more than five times, each of us. What is the ruling on my marrying his sister, or his marrying one of my sisters?

The Shaykh: Repeat.

The presenter: He says: I was breastfed by my cousin’s mother, and he was breastfed by my mother more than five times, each of us. What is the ruling on my marrying his sister, or his marrying one of my sisters between whom there was no breastfeeding?

Answer:
As long as he was breastfed by your mother, your sisters are forbidden to him, if the breastfeeding was, as you said, five breastfeedings or more; because your sisters are his sisters through breastfeeding. Likewise, as long as you were breastfed by his mother, all of his sisters are forbidden to you; because they are your sisters, if those are from the mother, from that woman who breastfed you both. Yes.

The presenter: May Allah reward you with good.