Answer:
The novel is a story-within-a-story. Creech writes about Sal's road trip to Idaho with her eccentric grandparents, and during the trip, Sal tells her grandparents about her friend Phoebe Winterbottom and the disappearance of Phoebe's mother.
 
        
             
        
        
        
The poem is stating, to stop and see what you have, take stock, before you neglect or lose “it”.
“A bird in the hand is worth more than two in a bush”!
        
             
        
        
        
A. Jack kerouac's is the answer to your question
        
             
        
        
        
Whitman celebrates the common person