For instance when the characters Dallas, Ponyboy, and Johnny exchange items. All the deaths that happened. Johnny killed Bob and Dallas got shot by the police. Darry, Soda, and Pony are all brothers. Despite all their similarities they also have some differences.
One difference is how they say where they live. They say north, east, south, and west. The kids who live on the east side have enough money as to the kids who live on the west side do not. Many places are divided by many lines, like the kids from the east