The way in which the author uses the events in the story to illustrate the theme that small gestures can have a lasting impact is by showing that Cameron and Cassie were helpful to Jackie after her fall.
What is a Theme?
This is the central idea or the unifying idea that an author wants to convey to his readers.
Hence, we can see that the supporting detail which can be used to support the answer is the fact that while Jackie wanted to fit in and had a nasty fall, Cameron and Cassie were nice to her which restored Jackie's confidence.
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