DNA test reveals man has nine half-siblings linked to his mother’s former fertility doctorA routine ancestry DNA test turned into a deeply disturbing family discovery when Joseph Laedtke learned he had nine half-siblings. The unexpected matches appeared to connect him to the Wisconsin fertility doctor who treated his mother decades ago. She had believed her son was conceived using donor sperm after years of fertility treatment. She said the doctor told her the man was unlikely to donate again and was from another state. It was only then that he learned his parents had used donor sperm.