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: Alex was at the lake with his family. Sentence2: Some of the people were out on a boat. Sentence3: Suddenly an intense storm came rolling in. Sentence4: Everyone was worried about the people in the boat. Sentence5: Luckily, they had stopped on a beach and kept themselves safe.
Some of the people, His family, Alex