 Eun-chae's father did this because thought he was "saving" Audrey's reputation because if Korean society was to find out about her affair then she would be disgraced.Audrey had adopted Choi Yoon in memory of her son, still believing Moo-hyuk was dead.Once Moo-hyuk discovers this, Eun-chae's father admits to the truth, and tells him that he is willing to accept any punishment.