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: Ryan woke up one morning with a swollen foot. Sentence2: His mom took him to the doctor to see what was wrong. Sentence3: The doctor told him it looked like his toe was infected. Sentence4: They had to do surgery on it. Sentence5: Ryan felt better the next morning.
A:
Mom, Ryan, Doctor