Definition: 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.
Input: Sentence1: Tim's dog was very sick. Sentence2: Tim's dog wasn't eating or drinking. Sentence3: Tim took his dog to the vet. Sentence4: The vet gave Tim's dog a shot. Sentence5: Tim's dog slept for two days straight and then died.
Output:
Tim, The vet, Tim's dog