Responses
I think what they're saying is that it was the little brother who was in England not hajin. The younger brother is not the dad's son he's the product of am affair.
It's a bit confusing it's just mystery over mystery
So uh the white, haired guy and Hajin were switched?? So Hajin is actually the illegitimate son and the white haired guy is the biological one because the mom told the dad this line "you know what that kid means to us" So yeah I'm probably guessing that's why the mom don't like Hajin since he's not her son