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.
Q: Sentence1: Stan opened the mail one day. Sentence2: He noticed his electric bill was more expensive than usual. Sentence3: He asked everyone in the family if they knew why. Sentence4: His oldest son admitted to never turning off his computer. Sentence5: Stan asked him to start doing so and he obliged.
A:
Stan, Family, Son