Who is the narrator, can she or he read minds, and, more importantly, can we trust her or him?
First Person (Central Narrator)
Dear Mr. Henshaw is made up entirely of letters or diary entries written by Leigh, which means that everything is from Leigh's perspective. The only time we get another point of view is when Leigh quotes what someone else says.
Leigh never shows the reader that he's an unreliable narrator. The adults don't call him a liar, and he doesn't tell us one thing here and change his story over there. So when he says other people are doing such-and-such or that they look like this or that, we believe him.
However, since this is from a young boy's perspective who's writing as he experiences everything (versus writing what happened a long time ago), he's reliable but not always truthful. But that's only because he doesn't always know what's true in the moment.
Confused? Let Shmoop explain.
Mom says how much she loved riding with Dad, and Leigh thinks, "Maybe if I hadn't been born, Mom might still be riding with Dad. Maybe I'm to blame for everything" (34.4). These are totally valid thoughts in the moment, but also totally wrong. We (and Leigh) find out later that Mom "had had enough of highways and truck stops" (39.14) and assures him that it wasn't his fault. Mom sets the record straight for Leigh, telling him she was done with all the traveling, and it had nothing to do with him.
Whew. Now Leigh knows that those worries he had before were all false.
Another example comes at the very end. Dad finally comes to visit (hooray) and then tells Leigh he's only in the area to pick up a shipment of broccoli (boo).
Leigh writes, "I felt let down and my feelings hurt. They hurt so much I couldn't think of anything to say" (60.14). Dad is only there for the broccoli.
Then Dad leaves, and Leigh thinks about it a little more. He realizes "maybe it was broccoli that brought Dad to Salinas, but he had come the rest of the way because he really wanted to see us" (60.45). It's not that Leigh is wrong when his feelings are hurt. It's that his perspective changes after he has thought things over.
Having a first-person narrator means that the reader is taken along for the ride on the character's emotional roller coaster. And sometimes, we're talking SheiKra.