The Boy in The Striped Pajamas tells the tragic story of two boys, one German and the other Jewish, caught up in the Holocaust, and the effects of their lives in, or close to "Out-With" as Bruno calls it. The boys meet in chapter 10 when Bruno decides to explore, despite having been forbidden from doing so, with "No Exceptions!" The boys connect immediately, despite being separated by "the fence" and Bruno is excited because "We're like twins," discovering that they share a birthday. Shmuel is less convinced- "a little bit." Shmuel is far more aware of their differences.
Bruno does most of the talking and asking questions and it is obvious to the reader that he has been indoctrinated when he talks about how "Germany is the greatest of all countries." Ironically, Bruno thinks that Shmuel is lucky in so many ways, never realizing the extent of the abuse. He is disappointed when he eventually goes under the fence and he does not see the happy families picnicking and enjoying themselves such as he expected but still his expectations remain positive. On the other hand, Shmuel has long since accepted his situation and does try to tell Bruno, warning him and wondering "why you're so anxious to come across here anyway... It's not very nice." Shmuel seems to realise that Bruno will not really understand and "blinked and opened his mouth to say something but then thought better of it."
John Boyne retains this distinction between the boys to intensify the tragedy of the historical reality but Bruno does notice "Our hands... 'They're so different." Shmuel's hands are almost skeleton-like. The boy's relationship begins to change as, under the fence, they "shook hands and smiled at each other." After Bruno has his hair shaved, when Gretel, his sister, finds lice in her hair, the irony of the situation intensifies as now Bruno looks even more like his friend "only fatter."Ultimately, the boys differences will become immaterial, their allegiances will be unnoticed and their innocence absolute. Their relationship will also change at this point as Bruno, forever questioning, just reassures Shmuel by squeezing his hand, recognizing his fear and comforting him in his own way - "My best friend for life."