Rather than be the usual "you're imagining things, there's no such thing as ghosts" etc, he seemed to think she really was seeing something. He even got annoyed at Elise for linking the ghosts to Dalton's condition.
shareYes me too. Probably because deep in his subconscious he "knew" that he'd had previous dealings with the supernatural because he was, as Elise put it, "an accomplished traveler" or something like that. Josh knew about The Further even though he didn't come out and say so. Renal's claim want completely farfetched.
shareWell he had moved because their last house was haunted so for him to doubt her this time around wouldn't really have made sense.
Hey! You're not old enough to drink! Now go and die for your country!!!
I think his visions of the ghost watching over him as a kid are his slow realizations of his own past. Almost like PTSD, he blocked out a lot of his childhood, and it slowly comes back to him because of the same thing happening to his son. I don't think he legitimately KNEW, but he was realizing what was going on as the film progressed.
shareI felt like he did doubt her and kind of discredit her fears in the beginning
share