What are clues in chapter 5-7 that Sandy's pregnant?
In Chapter Seven, Soda Pop and Steve make plans about throwing a big victory party after defeating the Socs. Ponyboy, just to add to the conversation, inquires if Soda would take his girlfriend Sandy to the pary. The room instantly silences. This is the first clue that not all is well with Sandy and Soda's relationship.
Hinton uses the characters' reactions to Pony's remark to reveal the truth about Sandy's pregnancy. First, Soda Pop's ears turn red and mumbles something about Sandy going to Florida to live with her grandmother. Then Steve becomes angry that Ponyboy has brought up a clearly sensitive issue:
"Does he have to draw you a picture? It was either that or get married, and her parents almost hit the roof at the idea of her marryin' a sixteen-year-old kid" (111).
The reader can easily draw their own conclusion about why Sandy would have to get married or move to Florida--she must be pregnant. Pony's reaction confirms it, wondering "Soda was no innocent [...] and his bragging was as loud as anyone's. But never about Sandy" (111). Hinton's conversational clues and use of character body language makes this awkward moment of truth feel genuine and realistic to the reader.