"[Byron] dropped out of the tree like a superhero."
Whenever Byron commits an infraction, he always appears to be proud of himself. He does not understand why his actions are wrong, nor does he anticipate the consequences he will face -- aspects of his behavior that are signs of his lingering immaturity. This simile likens Byron to a superhero, and suggests the smug, proud look on his face in this moment. To himself, Byron really is a superhero.
"Momma's voice got strange, hissing like a snake."
This descriptive simile, used when Wilona is furious with Byron for playing with matches, emphasizes the extent of Wilona's anger. The snake specifically is an animal typically associated with malice and evil, so comparing Wilona to a snake clearly underscores how fed up she is with Byron and his antics. It is only shortly after this that Daniel and Wilona decide to do something about Byron once and for all.
"Haven't any of you wondered why you've been sleeping like a little herd of angels?"
During the car ride to Birmingham, Daniel compares his family to a herd of angels while they sleep in order to emphasize the difference between their sleeping state and their waking state. When the Watson children are awake, they are far from little angels, since they are constantly arguing with each other or complaining about the distance remaining in the trip.
"Grandma Sands laughed just like the Wicked Witch of the West."
This simile fits nicely into the image of Grandma Sands that the Watson parents' stories have created. Grandma Sands is meant to be a kind of Wicked Witch of the West to Byron, an authority figure who will snap him out of his delinquency and teach him that the world is about more than jokes and tricks. Kenny has always envisioned Grandma Sands as something akin to a witch; even though Grandma Sands reveals a much softer side to her relatives, she is still pretty strict.
"It looked like a river of scared brown bodies was being jerked in the same direction that By had gone."
This chilling simile paints a clear and frightening picture of all the people in the neighborhood rushing, afraid, to the scene of the church bombing. Combining many people into a single "river" emphasizes their unity in this moment; they are all bound together by the same fears, racing to the same destination and united against the act of terror that has just occurred.
The Watsons Go to Birmingham - 1963 Questions and Answers
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