In the story, Doodle is a disabled boy whose older brother cares for him and teaches him to walk. However, Brother frequently grows impatient with him. Doodle dies at the end of the story.
Doodle is strongly associated with nature, such as with the Old Woman Swamp. When he first sees it, he cries:
It's so pretty, Brother, so pretty.
Brother often takes him to the swamp. It is there that Brother teaches Doodle to walk, suggesting that Doodle derives strength from the natural world. The swamp is a place of hope that reflects Brother's expectation that Doodle can be made "normal."
The strongest way nature mirrors a character is through the scarlet ibis. Like Doodle, the bird is a beautiful creature of nature. But it is not destined to stay long in this world. Doodle is enamored with the beauty of the bird. When it tumbles out of the tree and dies, we learn:
It lay on the earth like a broken vase of red flowers, and even death could not mar its beauty.
Doodle wants to bury it.
The scarlet ibis foreshadows Doodle's own death. Right after the bird dies, Doodle and Brother go to the swamp. The storm that breaks out reflects Brother's confused emotions of love and cruelty. He is too young to be so burdened with taking care of this needy brother. Brother runs so that Doodle can't keep up with him. When Doodle dies, he looks very similar to the scarlet ibis:
He had been bleeding from the mouth, and his neck and the front of his shirt were stained a brilliant red.
Brother has realized, just before Doodle dies, that Doodle won't ever be like the other children at school. Doodle is a child of nature, and feels at home in the swamp. In a sense, Doodle escapes his outsider fate by dying where he feels most at home.