What is a quote from Ponyboy that depicts how much he has changed and matured as an individual?

In Chapter 12, Ponyboy and Darry begin arguing at the dinner table about Ponyboy completing his English paper. Ponyboy mentions that it is their fourth fight this week, and brings Sodapop into the conversation. Sodapop has just received his letter to Sandy unopened and takes off running out of the house. Ponyboy and Darry chase after Sodapop, and when they catch him, Soda tells them that he's sick of them fighting. Sodapop tells Ponyboy that Darry cares about him, and then tells Darry that he needs to try to understand Ponyboy better. Ponyboy thinks to himself,

"Darry looked real worried. I suddenly realized that Darry was only twenty, that he wasn't so much older that he couldn't feel scared or hurt and as lost as the rest of us. I saw that I had expected Darry to do all the understanding without even trying to understand him. And he had given up a lot for Soda and me." (Hinton 176)

At the beginning of the novel, Ponyboy does not get along with his older brother Darry. He believes that Darry is hard on him and doesn't care about him. Initially, Ponyboy does not try to understand his older brother. As the novel progresses, Ponyboy gradually develops an understanding of Darry. After he sees Darry for the first time while he is in the hospital, he realizes the Darry cares about him. Ponyboy displays his maturation in the last chapter by realizing that Darry has made many sacrifices for him and Sodapop. Ponyboy gains perspective on his older brother by realizing that Darry is only twenty years old and has a lot of responsibility. Ponyboy is aware that he has neglected Darry's feelings and recognizes that he needs to try understanding Darry for once.