Thanlungliu Panmei

The drama is funny and interesting but something in the storyline seems abit off to me, Firstly why did they get rid of Lee yool mother for his father to be a king, can they just let his mother live and be a king? Secondly, Who is the late king? and Why did they saw only the girl's father killed? what is the relation between the girls father and the throne? Thirdly, won daek is the name which Hong shim made it up because she don't want to get married but why did she seems so surprised about won daek can't remember anything and about him being homeless maybe i miss something about what her adopted father had told her but there's something that doesn't make sense.. .