Will you be able to live with yourself knowing what I'm going to make you do? Poor little Joseph couldn't..."
—Ruvik talking about Joseph to Sebastian
Though they've never been interacting on screen, we can use evidence to figure out what their relationship is like. Ruvik seems to treat Joseph as if he's a pawn in his plans. Like Connelly, Joseph appears to be much more susceptible to Ruvik's influence then Sebastian or Juli. However he is not as susceptible as Connelly as he is seen fighting against the urges to turn into a haunted. Ruvik also mentions Joseph and how because of trying to kill Juli that he can't live with himself. It's obvious that he used Joseph as an example to show Juli that the people you trust can turn on you in an instant. Basically he doesn't see anymore use in Joseph other than a pawn. Probably because there is nothing they can relate with.