Why is it significant that Jem had been crying?
In Chapter 7, Jem and Scout find several items in the knothole of the Radley tree. They find a ball of gray twine, two small figurines carved out of soap, a whole pack of chewing gum, a tarnished spelling bee medal, and a pocket watch with an aluminum knife. Jem tells Scout that he thinks they should write a letter to whoever has been leaving them the gifts in the knothole. They thank the mysterious person for leaving them gifts and sign their names. The next morning Jem goes to place the envelope into the knothole, only to find out that the knothole has been filled in with cement. The next day, Jem asks Nathan Radley why he filled the knothole with cement, and Nathan tells Jem that the tree was dying. He says, "You plug 'em with cement when they're sick. You ought to know that, Jem" (Lee 83). That evening, Jem asks Atticus if he thinks that the tree is dying. Atticus says, "Why no, son, I don't think so. Look at the leaves, they're all green and full, no brown patches anywhere---" (Lee 84). Jem then asks Atticus if he thinks the tree is sick and Atticus says, "That tree's as healthy as you are, Jem. Why?" (Lee 84). Jem explains to Atticus that Nathan told him it was dying. After their conversation, Jem stands on the porch with his back against the pillar in deep thought. When he finally decides to come back into the house, Scout mentions that she can tell that he had been crying.
It is significant that Jem is crying because this is the first time Jem realizes that an adult has lied to him. Before speaking with Nathan, Jem was confident in the fact that adults only told the truth. When Nathan's answer doesn't satisfy Jem, he goes to his father because he knows Atticus will be honest. Atticus points out the fact that the tree has full, green leaves and is perfectly healthy. Jem is bothered by the fact that Nathan lied to him, which is one reason he begins to cry. Jem also cries because he knows that he has lost his opportunity to communicate with Boo Radley. Throughout the chapter, Jem is conflicted about the identity of the person giving them gifts. Deep down, Jem knows that Boo Radley is responsible, and after he finds out that the knothole has been filled in with cement, he becomes heartbroken.