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: My cat went missing the other night! Sentence2: I tried to find her for days. Sentence3: About a week later, she came back. Sentence4: But to my surprise, she was pregnant! Sentence5: Now, I have to find a place for the kittens.
I (myself), Kittens, Cat