I think the casket is a symbol of death and it is also a symbol of cruelty of the narrator that he took Doodle to see it and touch it to emphasize that they thought he was going to die so needed to be brought face to face with it.
You can revise your claim to make it sound more original or specific by changing the hook to a very different but still effective one, you should have different types of redirect to stand out
Making notes about specific parts of the text and or keeping a journal of your interpretations. Hope this helps! ;D
