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: Abby was not having a good day at all. Sentence2: In fact, Abby was told by her mother she had breast cancer. Sentence3: Abby wanted to just crawl up in a hole and sulk for her mother. Sentence4: However, Abby's mother assured her that her cancer was treatable. Sentence5: Abby was still very sad at her mother's diagnosis.
Output:
Abby's mother, Abby