Two Mothers

Hwa-young believes that Yeon-hee, her brother's ex-girlfriend, drove him to his death. When the unhappily married Yeon-hee is diagnosed with uterine cancer, Hwa-young volunteers to become a surrogate mother for her, all the while planning her revenge. Hwa-young conceives and gives birth, lets Yeon-hee raise the child, then destroys Yeon-hee by trying to take the child back. Later, Yeon-hee tries her best to get her child back. Yeon-hee's husband regrets for letting Yeon-hee go. [About] Cuckoo is a 2014 South Korean daily drama starring Jang Seo-Hee, Lee Chae-Young, Hwang Dong-Joo and Kim Kyung-Nam. It premiered on KBS2 on June 3, 2014, airing every Monday to Friday at 19:50 for 102 episodes [Source: Wikipedia]