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.
Input: Sentence1: Lacy was pregnant and due in five weeks. Sentence2: But one day, she had a headache. Sentence3: She forgot which medications were safe to take while pregnant. Sentence4: She called her doctor to double check what was okay. Sentence5: She followed his instructions carefully.
Output:
Lacy, Doctor