Think he could get a professorship?
Your son's second cousin is your first cousin once removed. If the first cousin once removed is the son of your first cousin. So the children are second cousins. Their children are third cousins but the grandson of your first cousin is your first cousin twice removed and his son is your first cousin thrice removed. Dont marry him, I don't think it is a good idea unless you are mary Kaye LeTourneau.