Given the task definition and input, reply with output. 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: Glenn had never learned to swim as a child. Sentence2: He wanted to go to the pool with his friends. Sentence3: His apprehension prevented him from having fun. Sentence4: One day he went to the pool for private lessons. Sentence5: This gave Glenn the courage to go swimming with his friends.
Friends, Glenn