What are some examples of how the narrator (Doodle's brother) was mean or cruel to poor Doodle?

The narrator, known only as "Brother," is cruel to Doodle in various ways. He wheels Doodle around much too fast and Doodle falls out of the little cart. He takes Doodle up to see the coffin that was meant to be his. He also pushes Doodle beyond Doodle's limits purely out of pride. The narrator cannot bear the thought of having a brother who is "different" when he starts school.