Unsolved mystries and the German spy/

Radio 5 live tonight is asking about mysteries one has never solved. Mine goes right back to the war time. My mother worked for a German Jew who had escaped just before the war. She had been helped to do so by a Nazi lover. My dad and I, for various reasons, in later years often wondered if she had been a spy. We felt if she had it would have been because of pressure but who knows, it might not. I can’t say how but she had access to knowledge of the troops which were numerous in the town. We never did come to any conclusions. Perhaps it was because dad did not like her very much.