It's a curious thing how ghosts are intertwined with relationships that have a strong emotional aspect to them. In this case, Poppy's grief made her vulnerable to ghostly apparitions. Shakespeare depicted this well in Hamlet when the young prince was vulnerable after losing his father and his friends cautioned him against being seduced by familiar spirits who could assume the shape of a lost loved one and tempt him to a cliff where he might fall into the flood (sea). But this series, Haunts, is about to take an unexpected turn so be advised, lol.