Hannah, I don't think you get how it works! if your MOTHER is Jewish you are Jewish and that's according to the Orthodox. His son on the other hand would not be... oh and in Judaism we don't recognize Christian conversions, so his mother was always Jewish even after her conversion.
Israeli woman, 65, stabbed in Bedouin town of Rahat (Haaretz)
from the article: Princeton president uncovers family secret - that he is Jewish