From the book, the helper dog spazzing out when she first sees the simple dog, snarling and clawing at the car window with wild eyes. To make it worse, the helper dog is a German Shepherd mix — she's pretty big and strong for a dog.
In an Adult Fear kind of way, the story about how Allie's mom got lost in the woods with her two children with no way to get home and having to desperately put on a brave face so as not to terrify them.
The part in "Texas" where Allie wanders alone into a rough neighborhood looking for a grocery store. It's terrifying enough that the houses here are described as having bars in all the windows and there are bullet holes in some of the cars parked along the street, but Allie is also delirious from a high fever and has absolutely no idea where she's going.