In The Watsons Go to Birmingham, on pages 138–140, in chapter 10, Kenny asks for a second glass of Kool-Aid even though it tasted like "grape medicine" because it was his turn to eat his momma's peanut sandwiches. He says that she would layer the sandwiches with so much spread that he needed something to wash it down with "in case you start choking."

The Watsons—Kenny, Joetta, Byron, and their parents—are taking a road trip from Michigan to Birmingham, Alabama in their "brown bomber" to see their grandma Sands and deliver Byron to her. Byron, Kenny's older brother, has been misbehaving and hanging out with the wrong people. They are hoping the strong and religious grandmother Sands can straighten him out.

When they reach Birmingham, however, they find themselves in the middle of a race war. At one point, Kenny thinks his sister is one of the victims of the 16th Street Baptist Church bombing. Fortunately, he finds her safe at home.

Kenny asks for more Kool-Aid because he has a peanut butter and jelly sandwich that has too much peanut butter on it.  Regardless of how the Kool-Aid tastes, it is better to have something to drink when eating such a sandwich.

In Chapter 10, the Watson family is driving down to Birmingham and has just entered Ohio.  They are stopped at a rest area for lunch.  Momma has made Kool-Aid using water from a pump at the rest area.  The Kool-Aid taste metallic and like medicine.  Everyone except Momma hates it and they all dump theirs out when she isn’t looking.  But Kenny is having a peanut butter and jelly sandwich.  This means that he needs the Kool-Aid because

Momma always puts too much peanut butter on the sandwich and you’ve got to have something to wash it down in case you start choking.

So, even though Kenny hates the Kool-Aid, he asks for seconds because he dumped his first cup but needs something to drink with the sandwich.