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: Kenneth had not spoken with his mother in 15 Year's. Sentence2: They had both forgotten why they had started fighting. Sentence3: Finally Kenneth called his mother to talk. Sentence4: They were both relieved to speak with each other. Sentence5: Kenneth decided never to allow another argument last so long.
Kenneth