Family Lineage and Timeline

It's quite confusing

So the father already married and had a child, that child is our FL
Then at one point the father had incest with his sister, and that is when the father and FL's mother got divorced
From this point onward, the father living with his sister and their child which is Young ho
Then the father died and so the sister (aka Young ho's mother) and Young ho went into hiding in shaman place
Then Young ho's mother made a deal with the uncle (aka the father's brother, aka her brother too right) that the land should be given to Young ho
But then the uncle died and since Young ho is not in the register, the land goes to our FL
and this is when story start

Is this correct?

 Carpediem:

It's quite confusing

So the father already married and had a child, that child is our FL
Then at one point the father had incest with his sister, and that is when the father and FL's mother got divorced
From this point onward, the father living with his sister and their child which is Young ho
Then the father died and so the sister (aka Young ho's mother) and Young ho went into hiding in shaman place
Then Young ho's mother made a deal with the uncle (aka the father's brother, aka her brother too right) that the land should be given to Young ho
But then the uncle died and since Young ho is not in the register, the land goes to our FL
and this is when story start

Is this correct?

From what I understood, the father and his sister always had a thing for each other - Hence, why those two were closer to each other compared to the other brother (the one who overdosed in Ep. 1.) 

However, as they got older, the father marries the female lead's (Yoon Seoha) mother and the sister marries a man, but despite this, the siblings kept coming back to each other to continue their secret relationship. 

I guess throughout their sneaking around-period, they get caught by their neighbors and rumors start to spread about their secret romance and it's during this time the sister's husband divorces her (due to shame) and Yoon Seoha' mother brings the father to a shaman to "get rid of the demon that has possessed him" (due to his infidelity, but mostly because of his incest relationship.) 

As a result, he leaves Yoon Seoha and her mother (They never got a divorce, their marriage is still legal - As stated earlier on in the series - The father simply left them without a notice) and moves in with his sister instead, and shortly after the sister gets pregnant by him - Which is how Kim Youngho gets in to the picture.

By the way, I don't think the sister made a deal with her brother (The one who overdosed and originally owned the land.) He had no idea that his two siblings were in a incest relationship until she herself came forward to him (Shown in a scene in the last two eps.) 

I guess the reason she killed anyone who stood in her way, or had any type of connection to the gravesite was because she solely wanted her own son (Youngho) to inherit it. Due to him being socially and emotionally unstable it's hard for him to get a stable career and earn a decent amount of money thus live a good life - Therefore, I assume, his mother (the sister) wanted to provide something good for him in the long-run and her killing off any opposition for the gravesite would be just that.