| Quote #1
He'd had a nightmare. Well, not a nightmare. The nightmare. The one he'd been having a lot lately. The one with the darkness and the wind and the screaming. The one with the hands slipping from his grasp, no matter how hard he tried to hold on. (1.3)
It's interesting that Conor says "the screaming" and "the hands" instead of "his mother's screaming" or "his mother's hands." It's one more form of denial—if he doesn't say it's her in the dream, it might not be (though of course it is).
| Quote #2
Only a baby would have thought it really happened. Only a baby would believe that a tree—seriously, a tree—had walked down the hill and attacked the house. (2.11)
Here's an example of the dark humor Ness intersperses throughout the book to lighten the mood a bit. We see what Conor's thinking, and we're with him in wondering what's up. We're just as dumbfounded as he is as to what's real and what's in his head.
| Quote #3
When Conor started having that nightmare, that's when Harry noticed him, like a secret mark had been placed on him that only Harry could see. (3.8)
Bullies often bully out of fear. Harry could very well be afraid that what's happening to Conor's mom will happen to his, and mocking Conor is a way of mocking death. At the very least, it's a clever parallel between Conor's nightmarish real world (in which he's bullied by Harry), and his all-too-real nightmares (in which he's bullied by death).