What is the ruling on marrying the daughter of a maternal aunt through breastfeeding?

The questioner : He says: What is your opinion regarding a boy who was raised by his maternal grandmother? Is it permissible for him to marry his maternal aunt’s daughter? Because she was not raised by her grandmother, or does the boy become the maternal uncle of the girl through breastfeeding?

The Shaykh : The boy here is the maternal uncle of his maternal aunt’s daughter through breastfeeding, because when he was raised by his grandmother, he became a brother to his maternal aunt and to his mother as well. Therefore, his maternal aunt’s daughters and his maternal uncles’ daughters are among those forbidden to him, because he is their maternal uncle, or from their side.