About what did Holden write in Stradlater's composition?
When Holden agreed to do the English assignment for Stradlater, he was told that all he had to do was to describe an object. However, the story had reached a turning point and Holden was at the height of his preoccupation, therefore, he could not think on the directions, so he decided to write about a baseball glove that his brother Allie kept and wrote on with ink.
Slowly Holden begins to give way to his emotions and ended up finally writing how that was a bright and incredibly sweet kid with red hair, and that he died of leukemia. Holden does not give way to his emotions about the case, but he did say in the composition how when he got the call that his little brother had died he broke all the windows in the garage "just for the hell of it", and that he wanted to break the windows in the car too, but his hands were already messed up from breaking the garage windows.
This is when we, as readers, realize that Allie's death completely wounded Holden. Yet, he refuses to let out his true emotions about it.