Tear Jerker / Welcome to Dead House

• The first book has a bit of one: The whole town is populated by undead who are Weakened by the Light as well as apparently hating their existence. At the end Amanda succeeds at knocking down a tree and the sunlight destroys all the undead, who thank her for releasing them from their torment.
• A more mundane one from the same book but still sad: early in the book (before they discover the supernatural stuff going on) Amanda tells the reader about how she had to leave a lot of friends behind when they moved and, due to their new address being a four hour drive away, she won't get to see them much any more. There's a scene where her friend Kathy comes to visit. The two girls talk for a bit but then when it's time for Kathy to leave they both burst into tears.
• Upon discovering that the undead townspeople have been trying to kill her and her family, Amanda feels betrayed by her new "friend" Karen and says "but you seemed so nice!" Karen sadly replies, "I was nice until I moved here ..."
• The fate of Petey, the family dog. The townsfolk murder him and turn him into a zombie, just because he could sense what they really are. What's worse, unless he was destroyed along with the other undead, he's doomed to forever wander the streets of Dark Falls, never to be loved like a living dog again.