Is it permissible for the brother of the woman who breastfed the man five full feedings to marry the daughter of this man?

If a woman nurses a child five times within two years, the child becomes her foster son, and all those who are forbidden to her biological son are also forbidden to him. However, this prohibition is specific to the foster child and his children, not extending to his siblings or other relatives. Therefore, it is permissible for the daughter of the nursing woman's son to marry the brother of her foster sister. The prohibition does not extend to the foster child's siblings or those older than him. The nursing woman is also not forbidden to the foster child's father, his brothers, paternal uncles, or maternal uncles. Similarly, it is not forbidden for the nursing woman's husband to marry the foster child's mother, sister, paternal aunt, or maternal aunt. It is also permissible for the children of the nursing woman and her husband to marry the foster child's brothers and sisters.