Kim Jong-suk
Kim Jong-suk married Kim Il Sung in the Soviet Union, most likely in 1941. On February 16, 1941 (or 1942, sources vary), in the Soviet village of Vyatskoye, Kim Jong-suk gave birth to Kim Jong-il, who was given the Russian name "Yuri Irsenovich Kim," and the nickname "Yura." In 1944, Kim Jong-suk gave birth to a second son, Kim Man-il in Korean and "Alexander" or "Shura" in Russian. In 1946, she gave birth to daughter, Kim Kyŏng-hŭi. Augustina Vardugina, a woman from Vyatskoye, was in her teens when Kim Il-sung’s guerrilla group camped there. She remembers Kim Jong-suk, and how she would come to the village to barter military rations for chicken and eggs. Her son, Kim Jong-il, would be holding her hand.
Kim Hong-il (general)
However, Japanese secret police were increasingly active in Northeast China hunting down Korean partisans, and for his own safety Kim left the region and went to Shanghai. In 1926, he joined the Republic of China's National Revolutionary Army. His second son Kim Yong-jae was born around this time. He participated in the Northern Expedition, and was later stationed at Wusong Fort and then the . While assigned to the latter post, at the request of Kim Koo of the Provisional Government of the Republic of Korea, he provided Lee Bong-chang and Yun Bong-gil with the bombs used in 1932 in the Sakuradamon assassination attempt against Emperor Hirohito and the Hongkew Park attack on Japanese troops which killed General Yoshinori Shirakawa of the Shanghai Expeditionary Army. During the Shanghai War of 1932, he served as an intelligence officer with the 19th Route Army. In 1934, he was reassigned to the Luoyang branch of the Republic of China Military Academy, where he was in charge of a special course for Korean officer candidates in the ROC army.