Watched for the child roles only

TBH I only watched the first few episodes where the child counterpart of the leads were featured. And I'm not sure I'd be able to watch it completely in my lifetime. Anyway, from the few episodes I've seen, it's obvious that KYJ and YJG are brilliant actors. I even enjoyed the rivalry bet KYJ and KSH characters. This is maybe the 2nd historical kdrama I've watched so I was still a rookie watcher back then.