Unlike their father , all three of the Lasks ' sons had joined the German Communist Party by 1933 . Of the three of them , the youngest , Ernst , stayed for a time in Berlin working " underground " for the Communist Party ( which was now illegal ) . He was assigned to the party 's " anti-militarist " department which was in effect a cover name for the German Communist Party 's news service . He then fled , following his mother to Moscow , where he worked first for the Agriculture Institute and then for the International Economics and Politics Institute . However , at the end of June 1936 , a month after his thirtieth birthday , Ernst died of tuberculosis in the First University Clinic in Moscow hospital . The other two , Hermann and Ludwig , were arrested in 1938 , when the political purges in Moscow were still at their height . The middle son , Hermann , was banned to Arkhangelsk in the north where he lived with his widowed mother between 1941 and 1944 . He was eventually transferred to the Soviet " Labor army " , and returned to what remained in Germany in 1948 . The eldest son is sometimes identified in sources as Ludwig and sometimes as Lutz . Lutz , who had a degree in human economics ( '' " Volkswirtschaft " '' ) , was working at the Marx-Engels-Lenin Institute in Moscow when he was arrested . His detention included eight years in a camp at Kolyma in the Far East . Like his brother Hermann , he survived his time in the Soviet Union , but he was only permitted to return to Germany in 1953 . After Lutz was arrested , his wife , Dora , keen to avoid getting caught up in Stalin 's latest purge , left Moscow with their daughter Franziska . They crossed Europe and arrived in England towards the end of the summer of 1939 . Having avoided imprisonment by the Soviets , in London Dora was identified as an enemy alien and imprisoned in Holloway jail , and then " interned " on the Isle of Man . By the end of the war she had been released , and lived in England for the rest of her life : she died from kidney disease in 1952 , the year before the Soviets were finally persuaded to release her husband
political purges
Great Purge
Berta Lask