 Halban was divorced from his first wife, Els (nėe Andriesse, who later married the Czech physicist George Placzek), and in 1943 married Aline Strauss (nėe de Gunzbourg), who had escaped France in 1941 with her young son Michel.Following the Liberation of Paris in August 1944, Halban returned on a visit to London and Paris, where he saw Joliot-Curie for the first time since leaving France.Although he maintained that he did not divulge any nuclear secrets to his previous boss (Joliot-Curie), General Groves, the head of the Manhattan Project, had Halban removed from his job in Montreal, and replaced by John Cockcroft.