Forgotten Country is a 2012 novel by the American writer Catherine Chung and is published by Riverhead Books.
Their father felt he needed to flee to escape political persecution under an oppressive government.
The father and Komo are close, as they were orphaned when young and she took care of them, even when they lived with an uncle's family.
Janie's mother's older sister was kidnapped from a college dorm by North Korean soldiers who were taking girls, and never returned.
Janie has to find her sister before it is too late; her parents have returned to South Korea for recommended treatment for her father, whose cancer has metastasized.