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: Alvin's wife had been on a diet. Sentence2: He didn't like any of the food she had been cooking. Sentence3: Alvin would stop and pick up a burger on the way home from work. Sentence4: He ate very little of what she cooked. Sentence5: Alvin's wife lost weight, but he gained it.
Alvin, Wife