Is it permissible to marry the daughter of one’s maternal uncle with whom one was breastfed along with her sister?

This message is from Abd al-Rahman Ibrahim Ahmad, who says he is from the Arab Republic of Egypt. He says: I want to marry my maternal uncle’s daughter, but I was breastfed along with her elder sister. However, her elder sister is from her mother, and the second one—the one he wants to marry—is from her mother. Is it permissible for me to marry the one with whom I was breastfed along with her sister, or not?
Answer: If the questioner was breastfed by the fiancée’s stepmother (her father’s wife) or by her mother, then he is her brother. If he was breastfed by her stepmother or by her mother, he becomes her brother, even if he was not breastfed with her. As long as he was breastfed with her sister who came before her, he is her brother, or with her sister who came after her; it is all the same.
The point is: If he was breastfed by her stepmother or by her mother, he becomes her brother, either through the mother, the father, or both. Therefore, it is not permissible for him to marry her, whether he was breastfed with an elder sister or a younger sister. Yes.
The presenter: He also asks: Is she permissible for his younger brother or not?
The Shaykh: If his brother was not breastfed by her mother, she is permissible for him. If he was not breastfed by her mother or by her stepmother, and there is no breastfeeding between them, then she is permissible for him. As for the one who was breastfed by her mother or by her stepmother, she becomes his sister. Yes. But it must be noted that breastfeeding must be five sucklings or more, and it must be within the two-year period. The breastfeeding must be five distinct, established sucklings, and it must be within the two-year period. As for breastfeeding less than five times, or after the two-year period—the child is over two years old—this does not have an effect according to the correct opinion of the scholars of knowledge. Yes.