Mentioning an important rule regarding the spread of prohibition through breastfeeding.

The Shaykh : So the Messenger (peace and blessings be upon him) is a relative to her. This rule is important: breastfeeding affects whom? It affects the child and his descendants only, and it does not affect his relatives, such as a brother, uncle, father, or mother. However, if a child breastfeeds from a woman, all of her children become his brothers, whether they were born before or after him. The children of her husband also become his brothers, whether they were born before or after him. If you understand this, many issues that are difficult even for students of knowledge will become easy for you. There are many difficulties in issues of breastfeeding because a person does not have rules and guidelines. But if a person knows the rule, applying it becomes easy. The rule regarding the one who breastfeeds is that the prohibition extends to him and his descendants. The rule regarding the children of the woman who breastfed is that all of her children, male and female, from the husband with whom she breastfed while she was in his marriage, or from a previous husband, or from a later husband, all of them become what? Brothers to the one who breastfed. The children of the husband with whom she breastfed while she was in his marriage also become brothers to the one who breastfed, whether they are from a previous wife, a later wife, or the one she breastfed with; they all become brothers to the one who breastfed. If you know these rules, applying them becomes easy. Yes.