
Like fuck they'll gonna understand! XD
What kind of parent finds it ok for their kids to date.. even if they are not related. And these two need to understand that revealing their relationship would mean "bye bye happy family". Geez!

But this is not about how the kids feel atm??
The parents have no idea what has happened between them when they were young or what is happening between them now! So while the kids have had all this drama.. the mother and father had thought they have had this happy family for a long time.
If they decide to reveal their relationship to their parents.. they will of course ask why the sudden change? Then they have to explain that they have never thought about each other as siblings and haven't been close.. which means they also reveal that they have lied to their parents with a fake smile for many many years! XD
Either way.. I bet the outcome won't be super pretty, or wouldn't be if this wasn't a cute manga. But We'll see! I mean, the parents have a right to be upset, but I hope the family won't break apart.
This is why Soowon will never get Yona! She would burn him to a crisp with her savage words! ( ̄∇ ̄")