Other mistake: In the first shot when Carol Ann is being put to bed, the wicker headboard is backwards. I know this for a fact because I used to have the exact same headboard (queen size), and the large support frame faces the wall. The only thing you're supposed to see is a bunch of single swirls in the front. But they probably turned it that way so Carol Ann would have something to grab onto. White wicker furniture was very popular and cheap in the 1970s.
Other mistake: The night after burying the bird, a lightning strike projects an image of the tree outside onto the bedroom wall. However, the silhouette has nothing to do with the tree's shape.
Answer: It seems that the majority of the activity was focusing in on the Freeling house exclusively. It's not fully explained why they were the only house affected, but there are a number of possibilities. Possibly because it's where the highest concentration of spirits were at unrest. Possibly because it could be inferred that the Freelings moved in first given Steven was involved with the company that built the community, and thus they became the first targets. And possibly because they were trying to get to Carol-Anne since she was an easy target.
Also, it is mentioned in the movie that Carol Anne was actually born in the house. That likely caused everything to focus on her.
It was not meant that Carol Anne was literally born inside the house, just while the family was living there. It was just a casual colloquial expression Steven's boss made.
raywest ★