In Hinton's novel The Outsiders, Sodapop runs away from Ponyboy in chapter 12, basically at the end of the book. Darry and Ponyboy are arguing about Dally and Johnny and how best to grieve, remember them, and honor their brothers in arms. Sodapop is listening and the arguing pushes him over the edge. He has just gotten a letter back from Sandy. It is an unopened letter, which tells Soda that Sandy either never got the letter because someone else sent it back, or she sent it back because she does not want to hear from Sodapop again (more likely). Between the letter and the arguing, Soda has had it. He runs out and the reader learns that Sandy was pregnant, but not by Soda. That didn't matter to Soda; he wanted to marry her anyway, but she is no longer living in the area. She has moved to Florida. The boys quickly find Soda, listen to his concerns, agree to work on not fighting and bickering so much, and return home.