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: Once I had a babysitter who was kind of mean. Sentence2: She blew up a balloon and gave it to our cat. Sentence3: The cat played with the balloon until it popped. Sentence4: The babysitter laughed hysterically when the cat screamed and ran. Sentence5: I asked my parents to not use that babysitter any more.
I (myself), Babysitter, My parents, Cat