In Night by Elie Weisel, how was Elie brave?

I believe that Elie exhibits a great deal of bravery in the face of overwhelming violence and despair during his yearlong imprisonment in Nazi concentration camps. After all, Elie was only fifteen when he entered Auschwitz. Elie, although he laments throughout the book that he couldn't do more, displays particular courage in helping his father. There are three concrete examples of this bravery. First, when Elie's father is apparently a victim of the selection in section five, Elie does all he can to keep up the man's spirits when he is told to stay behind in the camp at Buna, facing almost certain extermination. When his father insists that Elie take his knife and spoon, Elie says,

"Don't talk like that, Father." (I felt that I would break into sobs.) "I don't want you to say that. Keep the spoon and knife. You need them as much as I do. We shall see each other again this evening, after work." 

Second, during the forced march from Buna to Gleiwitz, Elie is on the verge of collapsing. He confesses that death might be better than the physical pain he is enduring because of his injured foot and the bitter cold. Instead, he realizes that he must go on living for his father:

My father's presence was the only thing that stopped me...He was running at my side, out of breath, at the end of his strength, at his wit's end. I had no right to let myself die. What would he do without me? I was his only support.

Third, during another selection, Elie risks his life to save his father. When the prisoners were leaving Gleiwitz, the Nazis divided the men with the weak ones pointed to the left. Once Elie sees that his father is being sent to his death, he immediately runs after him creating a great deal of confusion. Amidst this chaos he is ultimately able to bring his father back to the right and safety:

I slipped in among the others. Several SS rushed to bring me back, creating such confusion that many of the people from the left were able to come back to the right—and among them, my father and myself. However, there were some shots and some dead.