No kids showing up for Trick or Treating?

With my game, only three kids showed up, all in costume. One was a kid living in the immediate neighborhood, one was a random NPC kid I've never seen before and one was a teenager (Cassandra Goth). They walked in, stuck their hands into that Spooky Day sweet bowl I had put out for them, yelled, and then walked straight out again. They did not knock on the door or try to interact with the resident sims. And they were gone so quickly that if I hadn't been watching I wouldn't have seen them.