Are the female cousins who disputed over the milk of the man forbidden to the one nursed by his grandmother from the milk of her second husband?

The rule regarding fosterage is that any two individuals who have suckled from the same breast become foster-siblings. Therefore, it is impermissible for either of them to marry the other, or the other's children. Based on this, the questioner's suckling from his grandmother makes him a maternal uncle to his female cousins (his mother's nieces), due to his sharing with their mother in suckling from the grandmother's breast.

It should be noted that the suckling which establishes prohibition and makes marriage unlawful must, according to the preponderant opinion, consist of five full and satisfying sucklings.