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: Tom was at the beach. Sentence2: He found a bottle with a message in it. Sentence3: The message had a contact e-mail. Sentence4: Tom e-mailed it and actually got a response. Sentence5: It was a pretty fun experience for him.
[A]: Tom

[Q]: Sentence1: Los Angeles has the worst parking ever. Sentence2: After driving around the same block five times I found a spot. Sentence3: I threw my car into park and hopped out. Sentence4: I came back in five minutes and already had a parking ticket. Sentence5: I didn't realize it was a park only on a Tuesday with a blue car zone.
[A]: I (myself)

[Q]: Sentence1: Alex had a young son. Sentence2: The boy was three years old. Sentence3: He still wasn't speaking. Sentence4: Alex told the doctor about his speech issue. Sentence5: Alex's son started to see a speech therapist.
[A]:
Speech therapist, Alex, Young son, Doctor