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: Alex had gotten into a situation at school. Sentence2: He vowed he would run away if his parents made him go back. Sentence3: They decided to homeschool Alex. Sentence4: He was ecstatic! Sentence5: Alex's joy dissipated when he realized it meant he couldn't slack off.
Alex's parents, Alex