It's one heck of a coincidence if they're not related. [ Which is to say, he definitely thinks they're related. ]

Ghosts definitely have the ability to negatively influence the emotions of people around them, especially ones that rate higher on the scale. These ghosts are definitely category tens. Feelings of dread, lightheadedness, even stuff like vertigo and hallucinations are pretty standard, though usually that kind of thing would affect everyone, not just a specific type of person.