My mother was raised by a Jewish woman (not her mother) who was an atheist, or better said, she became an atheist in the course of her life. This woman was married to a man called Jakob and she saw how he was arrested by the Gestapo in 1938. She thought that she would never see him again. She and her husband were both either members of the communist party or closely aligned. Communists got her false papers; she left Berlin with her baby daughter and went to Dsseldorf. There a German “blew her cover;” however, he did not hurt her, but help her. (She eventually found out that he was working for the American forces.) He got her good “clean” papers and also married her under her false name and adopted the baby daughter. She then had two daughters with the German. At the end of 1943 her husband, Jakob, found her again by chance. She could not even recognize him immediately. She took Jakob home, got in touch with her German husband who then got Jakob out of Germany and to an English speaking country. In August 1944 her and Jakob’s son was born. My question is this: are the two children she had with the German mamzerim? What is the status of her son? She was raised frum, but she never found the way back into a Jewish community. She raised her children as atheists. Although she spoke to me quite a bit in the last three years of her life, she flatly refused to speak about such issues.
All the chidren are Jewish and can join a Kehila. It should be done through a Beit Din. Rabbi Yosef Weitzen