Umm, yeah, I HATE that annoying, screeching prat, too! Did Spots manage to knock off that guy's headdress? Hae Jin, wasn't that his name? Hard to believe he was related to Mishil, but I imagine he takes after his father more.
My cheat sheet (the chart is at the bottom) says his name is Hajong. But I have noticed that the spelling of names varies, depending on who is translating. He is definitely the guy you are thinking of, the son of the minister and MiShil. You are right that the apple seems to have fallen far from the tree in his case. But then Mi Shil is a truly extraordinary person. It is a good thing there are not many people in the world anywhere near her caliber!