Mộng-Khanh was born in 1935. Mộng-Khanh's father was Việt and her mother was Mộng-Xuân Đặng. Her paternal grandparents were Lạn and Định Nguyễn. She had three brothers named Quang, Minh and Hải. She has a half-brother and a half-sister, named Lộc and Thanh-Nguyệt.