Detailed Instructions: 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.
Q: Sentence1: Heather has two sons and one step son, all of which are teenagers. Sentence2: It is summer vacation and they are all home from school. Sentence3: Heather can not keep food inside of the house because of them. Sentence4: Her sons are always hungry. Sentence5: Heather is happy it's almost time for them to go back to school.
A:
Her sons, Heather, Her step son