Sơn was born on February 21st, 1950. Sơn's father is Kim and his mother is Hảo Bùi thị. His paternal grandparents were Hãng and Lê Bùi-thị. He has four brothers and four sisters, named Đạt, Tuệ, Phong, Tiến, HIền, Phúc, An and Thanh. He is the second youngest of the nine children.