What is three best friends names in The Boy the Striped Pajamas?

The Boy in the Striped Pajamas focuses on the relationship between Bruno and his sister Gretel, and their friend, Shmuel. While Shmuel isn't technically a friend of Bruno's at the beginning of the story, they develop a close bond as the story progresses, making him a crucial character in the narrative.

It's important to note that Bruno and Shmuel's friendship isn't typical of the time period and the circumstances they find themselves in. Their connection is a testament to the innocence and humanity that can exist even in the face of unimaginable cruelty.