My Sister of Eternal Flower

Fa Lai Chu is a kind hearted and innocent woman with the IQ of a ten-year-old. When her parents passed away, she shoulders the responsibility to care for her younger sister and brother. While she is not able to bring home the bacon, she does an exceptional job protecting her siblings, though this often means bringing home hilarious troubles!
Taking charge of the family is Fa's younger sister Fa Lai Ping. She is determined to be successful by hook or by crook in order to take care of her mentally challenged sister and their younger brother, who is immature and has no business sense. She helps her supervisor, who is also her ex-boyfriend, Luk Ho Cheong, to betray the company they work at. In the meantime, the chairman of the company Tseung Sum, suffers a stroke. When he is in a coma, his playboy grandson Tseung Yik gets fired from work, but due to Fa's kindness, Yik does not end up on the street. It does not take long for Fa and Yik to fall in love with each other. However, when Sum comes around, he strongly opposes their "abnormal" relationship. Unwillingly, Yik breaks up with Fa and returns to the life which everybody perceives as normal.
(Source: DramaWiki)