What happened wasBy the last chapter, the Joad family are trying to find a way to build up the embankment to keep the train cars from flooding. All the men help once they realize Rose of Sharon has gone into labor and will give birth. Rose of Sharon is in agony all night as she tries to have her baby. But just as the baby comes, a tree falls due to the storm, breaks the embankment, and allows water to rush in.
The water destroys any possibility of the cars being able to drive and is also threatening the safety of everyone living in the train cars. Things go from bad to worse when they realize that Rose of Sharon's baby is stillborn. Their hard lives and lack of food had not allowed the baby to live. They put the baby in a cardboard box and send it down the river, unwilling to bury it, and then travel on from the flooding area.
The rain continues to pour, which drives them into a barn to take shelter. The Joads see that they are sharing the barn with a sickly man and his young son. The son explains that his father is dying of starvation. The food he had tried to feed his father was too much, so he needed something milder to give him, like milk. It's here that Ma Joad looks at Rose of Sharon, and they seem to come to an unspoken agreement. Ma shoves the rest of the family out of the barn, and Rose of Sharon lays next to the old man and breastfeeds him. The very last sentence states she had a 'mysterious smile.'
