What is buster brown a foreshadow of in the book The Watson's go to Birmingham?

In "The Watsons Go to Birmingham," Buster Brown's frozen hair is a foreshadowing of the extreme cold temperatures that the Watsons will later experience during their trip to Birmingham, which becomes a significant event in the story. This foreshadows the dangerous and life-changing events that will unfold as a result of the cold weather.