The answer to your question is: Why does Lennie not have it in "his" pocket? Because Lennie would have lost that card so George held it.
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What does Lennie have in his pocket?
Answer: Lennie carries a dead mouse in his pocket; however, Lennie's constant petting and strength kills the mouse, and George makes Lennie throw it away.
Answer:
In this story, each character symbolizes some cultural value that stands between a person and the fulfillment of his goals.
Explanation: