You will be given a definition of a task first, then some input of the task.
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: Jane's son was growing quickly. Sentence2: She was checking his height monthly to track his progress. Sentence3: Her son went out of town to visit his grandparents for the summer. Sentence4: When he returned Amy checked his height again. Sentence5: She was surprised to see he grew 6 inches in 2 months.
Output:
Jane, Grandparents, Amy, Son