What are some events from "The Boy In The Striped Pajamas" novel that relate to ALL the characters in the book?

The rise of Nazism and the Holocaust are two events that relate to all of the characters in The Boy in the Striped Pajamas.

The rise of the Nazi philosophy relates to Bruno's family. Bruno's grandparents, especially his grandmother, have to confront how their son, Bruno's father, embraces his future as a Nazi.  Bruno, Gretel, and their mother must move to Auschwitz because of father's "promotion" in the Nazi ranks.  Similarly, Lieutenant Kotler covets the career advancement his participation in Nazism affords him.  Herr Liszt's nationalist teachings reflect Nazi ideology. The emergence of Nazism also impacted those considered "outsiders."  Pavel and Shmuel are victims to it.  They are in Auschwitz, along with millions more, because the rise of Nazism deemed them as "enemies."  

The Holocaust is another event that relates to all of the characters.  On some level, it forces people to take action. On one side, people like Bruno's father and Lieutenant Kotler are perpetrators of the Holocaust.  They are part of the political and social agenda that targets those who are seen as "different." Kotler has no problem berating those he sees as "lesser" than him, something intrinsic to the Holocaust.  Bruno's father is in the position of power at Auschwitz, part of the Nazi death machinery that defined the Holocaust. At the other end of the spectrum, people like Bruno's grandmother stood opposed to the Holocaust, arguing that it is essential to speak out against a political and social program that targets other people.  Bruno's mother and sister take a stand against the Holocaust when they leave Auschwitz after Bruno's disappearance. Finally, Bruno repudiates the philosophy behind the Holocaust when he dons "striped pajamas" to help Shmuel find his father.  As he and Shmuel are herded into the gas chamber, the physical embodiment of the Holocaust, Bruno affirms friendship amidst hate and sadness.  The Holocaust and the rise of Nazism are two events that relate to all of the book's characters.