What is a good commentary conclusion on "The Scarlet Ibis"?

I imagine it took many years for the narrator to understand his own part in the life and death of his brother, Doodle, in the James Hurst short story, "The Scarlet Ibis." As a child who was not expected to live a very long life, Doodle surpassed all expectations, and his older brother should receive most of the credit. The brother pushed Doodle beyond all expectations, and through his efforts Doodle was able to enjoy some of the things a normal boy should--playing, swimming, climbing and dreaming. The narrator gave Doodle these attributes before the boy's heart gave out. That the older brother was present and first to discover the body of the blood-soaked little boy must have left him scarred and troubled. In his final moments of life, the older brother had left Doodle behind to die alone in the rain--a terrible thing to acknowledge for one so young. But as the years went by, the narrator must have come to understand that his action was a youthful mistake, and that Doodle could have never lived the life he led without his big brother close by.