Firstly, just because they look alike doesn't necessarily mean they're father and son. Some people look more like their aunts/uncle more than their parents because... well genetics. The brother and sister may not look alike because there are the so called dominant and recessive traits but they still have the similar genes. So maybe hyeonjin looks like his uncle because of this idea. Second, it's true that some abnormalities are caused beacuse of incest or in breeding within a family but that is not always the case. Some people develop abnormalities because the mother could have been going through something during pregnacy or maybe the person is just unlucky to be the "1 in a million" to have a weird condition. Otherwise your statement kinda says that people with rare ailments are the product of incestual relationships. Lastly, it could be important to him simply because it's his nephew that he wants to cure and he's his only family left. But then again it's not like we can dismiss your theory because there are shitty stories with clichè plot twists like that. So yeah... that's all my opinion really.
I also respect your opinion and I get what are you saying.Its just a theory of mine.But really the care he gives to his nephew is too much.But thank you for your reply.
(=・ω・=)
The way that uncle is overprotective and......this health problem that is rare.And tthe fact that we dont know about the father.And The uncle and nephew looking pretty similar.And the flashbacks with his sister.
Dont you think that the uncle is actually his father?I heard that when brothe and sister have a child,this child willbe born with an abnormal illness because they share the same blood.And this is why he is so absessed to cure him.What do you think?(づ￣ ³￣)づ