Is the brother of a paternal aunt through rada'ah considered mahram, or is it permissible to marry him?

"Suckling establishes what is prohibited by lineage. So, whoever suckles from a woman becomes a child to her and to her husband, the owner of the milk. This applies only to the suckled individual, not to his brothers and sisters. Therefore, the suckling relationship is confined to your paternal aunt only. Her suckling brother is not your paternal uncle through suckling, and it is permissible for you to marry him if no other suckling relationship is established between you."