That night after old Master Wong retired to the study, 2nd mistress entered the study with the kitchen knife but she was not able to execute her plan due to fear and the entry of Jia Ming. Jia ming decided to confront his father, because he knew old Master Wong wanted to bring 3rd mistress to Tian Jing to abort the baby which was Jia Ming’s. But given his weakness, Jia Ming was overpowered by old Master Wong. The confrontation took a toil on old Master Wong as well leaving him in the study suffering an asthmatic relapse. Ya Tou was all along hiding in the shadows, she stalked Jia Ming into the study. Seeing a weak old Master Wong, out of her psychotic love for Jia Ming, she suffocated old Master Wong with the cushion.

MURDERER: Ya Tou
(did u guessed correctly?)