Is there a prohibition on marriage between a young man and a young woman who are relatives, if there is a breastfeeding relationship, the details of which are uncertain, between the young man and the maternal aunt of the young woman (the paternal cousin of the young man's mother), where the time of breastfeeding, its number, and whether it was sufficient are not known with certainty?

If it is confirmed that you were suckled five times by the girl's grandmother within the two years [of infancy], then you are not permitted to marry her, because she would be your sister's daughter through suckling. However, as long as your mother is not certain that five sucklings occurred within the two years, the prohibition is not established; because suckling (رضاع) is not proven with doubt. And the suckling of the girl's maternal aunt by your mother does not prohibit your fiancée to you, for prohibition through suckling is specific to the suckled child and does not extend to their brothers, sisters, or their descendants.