How do images signify the literal and symbolic importance of objects to the development of the plot in "The Scarlet Ibis?"

The bleeding tree is a striking image because it bleeds sap and this symbolically foreshadows Doodle's death. The scarlet ibis brings even more symbolic clarity to this first comparison. The ibis is actually (literally) red and in this story, this is certainly symbolic of blood. The bleeding tree and the blood red color of the ibis all symbolize Doodle's blood at the end of the story. Despite Doodle's progress (at the hands of Brother's selfish motivation), these morbid images keep emerging.
Doodle's coffin is also an image that literally and symbolically refers to death. Doodle's father had it made when he was born, thinking he would not survive. Doodle survives, but they keep the coffin. Brother cruelly torments him the coffin, making sure he knows it was made for him.
Even after Doodle survives his infancy and learns to walk, the family keeps the coffin. "Within a few months Doodle had learned to walk well and his go-cart was put up in the barn loft (it's still there) beside his little mahogany coffin." That image of death is literally and symbolically still there. Between the bleeding tree, the scarlet ibis, and the coffin, the story constantly uses images to foreshadow blood and death.