Ruling on a man who married a woman and it was later established that her grandmother had breastfed him

Your Eminence! The first question in this session came from Yemen, from one of the brothers who used the initials (S. F. K). He says: If a man marries a woman and it is then established that her maternal grandmother breastfed him for a full year with light milk, and she is an old woman whose husband died a long time ago, is this marriage invalid? Please give us a ruling, may Allah reward you.
Answer: In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, and blessings and peace be upon the Messenger of Allah, and upon his family and his Companions, and upon those who follow his guidance. As for what follows:
It is established in the Noble Book and the pure Sunnah that breastfeeding makes prohibited what is prohibited by blood relation. Allah has specified in His Noble Book the prohibition of mothers through breastfeeding and sisters through breastfeeding. It is also established in the Sunnah from the Messenger of Allah (peace and blessings be upon him) that he said: They are all prohibited, just as they are prohibited by blood relation, by the explicit text of the Messenger of Allah (peace and blessings be upon him). So in this case, where a person was breastfed by his wife’s grandmother—her mother’s mother—he becomes her maternal uncle, the brother of her mother, if the old woman breastfed him for a full year. In fact, it is sufficient if she breastfed him five times. If she breastfed him five times, even in one sitting, he becomes her maternal uncle, the brother of her mother, and she becomes prohibited to him. This is because a sister’s daughter is prohibited by blood relation, so she is likewise prohibited through breastfeeding by the text of the Messenger (peace and blessings be upon him) and by the consensus of the scholars. This applies even if she is an old woman, and even if she is not currently married, having lost her husband a long time ago. The appearance of milk in her makes prohibited to the one she breastfed with it. Thus, this wife becomes the sister’s daughter of the husband, and he becomes her maternal uncle, so she is prohibited to him. The old woman becomes the mother of this husband and the grandmother of his children from this wife and from any other wife, because he has become her son through this breastfeeding. Even if the milk is light, as long as it is milk that nourishes him and he is nourished by it, it makes prohibited what is prohibited by blood relation. This applies even if she is not currently married, and even if she were a young woman, according to the correct view, who has not been married and has not been pregnant. If she produced milk and breastfed, she becomes the mother of the breastfed child, her brothers become his maternal uncles, and her sisters become his maternal aunts. The condition that the woman must have been pregnant is not sound, nor is the condition that she must have been married. As for this woman who has been pregnant and given birth, and whose husband died a long time ago, she fully meets the conditions according to the scholars. She has been pregnant and has given birth, so in any case, her milk is effective. Even if her husband died a long time ago, this milk with which she breastfed this man makes him the maternal uncle of his wife, so his wife becomes prohibited to him. Yes.