Pa and Uncle John, realizing that the rising water will eventually flood the cars, ask the other boxcar dwellers to work together to build an embankment to stem the water. They know it will take the strength of all the men working together. If some refuse, all will have to leave. With the support of the Wainwrights, the men leave to talk to the other campers.
Although she is not due yet, Rosasharn begins to have labor pains. When Pa returns, Ma tells him Rose of Sharon’s time is come. He is spurred to action, telling the men that the bank must be put up because his girl is having her baby. The men work feverishly in the downpour. As their labor continues through the night, they can hear screams coming from the Joad’s car. Soon after the screams abate, a large cottonwood tree, uprooted by the flooding, topples onto the bank, ripping a hole that allows the water to pour through. Al and the others race to their cars, but are unable to start them before the automobiles are surrounded by water.
Utterly dejected, the men return to the car to find that Rosasharn’s baby is born dead, shriveled and blue from lack of food. It is only a matter of time before the car floods, so Al suggests building a platform to keep their belongings dry. They spend the night huddled on the platform.
In the morning, Ma insists they leave to find higher ground. Al stays with Aggie and the Wainwrights. Carrying Rosasharn, Winfield, and Ruthie, Ma, Pa, and Uncle John set out along the flooded road. Drenched by a cloudburst, they decide to take shelter in an old barn. Once inside, they realize that they are not alone—a boy is kneeling next to the body of his father.
The boy tells Ma that his father is starving. The weakened man cannot keep down anything solid, but must have some nourishing liquid like soup or milk. Ma looks to Rose of Sharon, and as their eyes meet, there is silent agreement. Ma takes the rest of the family out of the barn, while Rose of Sharon sits next to the father. Loosening the blanket that covers her body, she offers her full breast of milk to the dying man. As he drinks, a mysterious smile appears on her lips.
