Although, I think that it would be implausible to interpret Brother's feelings for Doodle as hate, it is clear in the story that Brother hates the embarrassment he feels in connection to his little brother. For that reason, hate motivates Brother to teach Doodle to walk and increase his physical skills in other areas.
Unfortunately, Brother does not realize until it is too late that he loves Doodle. He pushes Doodle too hard and sacrifices him to his own pride. His love for Doodle causes the immense grief that he feels when he finds Doodle's body and when he thinks back to his childhood years later as the story's narrator.