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.

Example Input: Sentence1: The family arrives at the beach. Sentence2: Everyone puts on sunscreen. Sentence3: The son plays in the clear water. Sentence4: The daughter builds sand castles. Sentence5: The parents relax for the rest of the day.
Example Output: The parents, The daughter, The family, The son

Example Input: Sentence1: Marshall was incredibly nervous and had sweaty palms. Sentence2: He had vomited on his sweater already and practiced in the mirror. Sentence3: The rap battle began and Marshall rapped better than anyone there. Sentence4: Marshall won the rap battle and was awarded a medal. Sentence5: He eventually became famous and was awarded many other medals.
Example Output: Marshall

Example Input: Sentence1: Brad was looking forward to a rock concert. Sentence2: He bought tickets early. Sentence3: He was going to meet all his friends there. Sentence4: ON the weekend of the show he got in trouble. Sentence5: Brad was grounded and missed the concert.
Example Output:
Friends, Brad