The tone is apologetic because the narrator did everything for the wrong reasons and he is realizing that it was wrong now that his brother is dead.
"Doodle was just about the craziest brother a boy ever had. Of course, he wasn't crazy crazy like old Miss Leedie, who was in love with President Wilson and wrote him a letter every day, but was a nice crazy, like someone you meet in your dreams." The author uses figurative language to describe how crazy Doodle was.
In The Past
"The flower garden was strained with rotting brown magnolia petals and ironweeds grew rank amid the purple phlox." The author uses imagery to describe the garden.
"They named him William Armstrong, which is like tying a big tail on a small kite. Such a name sounds good only on a tombstone." This is a foreshadow because Doodle ends up dying.
"It was I who renamed him. When he crawled, he crawled backwards, as if he were in reverse and couldn't change gears." The author speaks in past tense because it happened long ago and it is referring to someone who has died.