Given the task definition and input, reply with output. In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.

Sentence1: The new upstairs neighbors have kids. Sentence2: They run around and are loud all day. Sentence3: They seem old enough to be in school. Sentence4: I called the authorities to see why they weren't. Sentence5: They showed up to investigate today.
Neighbors, I (myself), Kids, Authorities