Answer:
With Hurst making Brother as the narrative voice, we are able to reach deep into the feelings and emotions of the brother. It also reveals a sense of brotherly love, the want, and the need to make his sickly brother be a part of the 'normal' life of his peers and at times, even the selfish interests of the brother.
Explanation:
James Hurst's story "The Scarlet Ibis" revolves around the story of two brothers, one physically sick and the older brother trying to make sure his brother is capable of living the life of a typical child. Only identified as "Brother", the narrator is the older brother of the sickly William "Doodle" Armstrong, the story's main protagonist.
Brother's voice gives us an insight into the brotherly bond between the two siblings. He also gave us an in-depth look into what he really feels about his sibling's sickness, and what he wants for him in life. He pushes and tried to train him to make him stronger. At times, he even admitted it was for his own sake that he wants others to see his brother is like every child. He admits "It was bad enough having an invalid brother" and even wanted to smother him with a pillow. But a smile brought the human in him and he then decided to "train" and help him get better, be like every other kid.
Had the narrator been not the Brother, then all the inner feelings and emotions, the hatred and then the want to help, the pity and at times the selfishness will never be really revealed or known by the readers. So, through the voice of Brother, we understood and also know a great deal about the two brothers and the story's overall plot.