Describe the relationship between Bruno and his father.

In The Boy in the Striped Pyjamas, Bruno’s parents are raising him to be respectful of adults. Bruno and his father are polite toward each other but rather distant. It is his mother with whom he has a closer emotional relationship. Father seems to show affection with brief gestures, such as kissing him goodnight. Bruno’s attitude toward his father includes awestruck admiration for his physical attributes (e.g., his booming voice and loud footsteps) and the fact that he has an impressive uniform.
One reason for the distance between them seems to be that his father is keeping many aspects of his work secret. As he holds a fairly high rank in the Nazi regime, he must adhere to security regulations. This is especially true in regard to the concentration camps, as the Nazis tried to hide their true functions. Some of the direct consequences of the secrecy are Bruno’s ignorance of the events around him and, ultimately, his death.
The remoteness and secrecy are emphasized by the house rules. These require that no one enter Father’s office, which is “Out Of Bounds At All Times And No Exceptions.” Early in the novel, as the family prepares to move, Mother tells Bruno that they are moving because of Father’s job. He admits he does not know what it is.

"What kind of job?" asked Bruno, because if he was honest with himself—which he always tried to be—he wasn't entirely sure what job Father did.

He does not seem convinced that Father would miss him and his sister if they did not accompany him to the new job. When he complains to their maid, Maria, about having to leave home, he realizes Father has overheard him. His reaction furthers the impression of their distant relationship and suggests fear: “Father might . . . take him downstairs for a serious talking-to.”
When Bruno and the rest of the family arrive at Auschwitz, where Father had gone earlier, Father does not come to meet them. Instead, Bruno finds him in a meeting with other Nazi officers. When Father is alone in his office (still out of bounds), Bruno knocks and enters. Bruno is surprised that Father smiles warmly and then shakes his hand: “Father was not usually the type of man to give anyone a hug.”
When Bruno tells him that he thinks they should go home, Father says that Auschwitz is their new home and that they must stay because of the importance of the work and their duty. Bruno notes that he has never before tried to convince his father of anything. Their conversation continues with Father telling him a story about his own childhood and the necessity of sometimes doing things we do not want to do. When Bruno continues arguing his case, telling Father that Auschwitz is horrible and that he believes the Fury (Führer) sent him there as punishment, Father finally becomes impatient. He emphasizes the importance of following orders, calls Bruno insolent, and sends him to his room. Bruno admits that anger is unusual in his father and again emphasizes his distant attitude.

[I]f Bruno was honest with himself he would have admitted that Father rarely became angry; he became quiet and distant and always had his way in the end anyway—and rather than shouting at him or chasing him around the house, he simply shook his head and indicated that their debate was at an end.