In chapter 13, the family dog gets run over by a car, an event that foreshadows the death of Grandpa Joad. Grandpa Joad died of a stroke. The strain of the heat and his homesickness were too much for him to bear. The Joad family was just one of many that lost family members along the road. When Grandpa Joad died the family lost some hope that life will improve when they get to California. Grandpa Joad had at first been the big advocate of moving to California. His enthusiasm for the trip helped the other family members be excited about it too. The family, like many other families, buried dead family members illegally and kept moving west, but it seemed they buried their hope of a better life when they buried Grandpa Joad.
Pa Joad's character was an interesting one in that it depicted the loss of authority that comes with a man losing his ability to feed his family. It is as if a man's confidence is tied to his providing food and shelter for his own people. Ma Joad became the strong person in the family and held the family together during their trip. She endures sadness and hardship and drives the family onward when Pa Joad loses his ability to be a confident leader of his family. The most interesting picture of Ma Joad in the book is when she has endured all the hardship any person should ever have to bear and Tom reaches out to touch her. She thinks if he touches her she will fall apart she is so full of sadness. Steinbeck explains through her character how fragile the line is between hope and despair. .
Tom Joad undergoes the most dramatic change in the book. At the beginning of the book he is very self-interested. His friendship with Jim Casy teaches him so much. .
Tom was looking forward to being away from prison and enjoying his life and it turns out so badly. Grandpa Joad was the "law- in the beginning of the book. That power passed over Pa Joad when Grandpa died.