Is it permissible for a girl and a boy to marry if the girl's mother breastfed the boy twice, and the boy's grandmother breastfed the girl's brother once?

Scholars have differed regarding the amount of suckling that establishes prohibition (of marriage). The preponderant opinion is that it is five complete, satisfying sucklings within the two years (of infancy), based on the hadith (definition) of Aisha (may Allah be pleased with her) that the ten sucklings were abrogated by five known ones. Based on this, the two sucklings that the girl's mother received from the boy's mother have no effect. As for the suckling of the girl's brother by the boy's grandmother, it has no effect, even if it reached five sucklings.