Saying Kaddish for non-Jew

If a non-Jew tried to prevent someone from converting to Judaism, Kaddish will not rectify his soul. If a non-Jew behaved well to his son that converted – prayers will help lighten judgment on him. It is not clear whether saying prayers or Kaddish for him can benefit his soul, but the concensus is that it is not forbidden. Care should be taken in all the above that it should not appear anywhere as though he was Jewish, nor should it lend any legitimacy to intermarriage.