In chapter two, at the very end, Bruno is in their new home and looks out the window in his room.
"He put his face to the glass and saw what was out there, and this time when his eyes opened wide andhis mouth make the shape of an O, his hands stayed by his sides because something made him feel very cold and unsafe. (pg 20)
When Bruno decides to investigate the camp, he knows that something is wrong. We see the camp through the eyes of Bruno, a child and an innocent, but even he feels that something isn't right.
"The one thing Bruno tried not to think about was that he had been told on countless occasions by both Mother and Father that he was not allowed to walk in this direction, that he was not allowed anywhere near the fence or the camp, and most particularly that exploration was banned at Out-With. With No Exceptions." (pg 103)
This foreshadows that the fence and camp are dangerous. They do not want him anywhere close.
When he sees that everyone behind the fence was wearing the striped pajamas, and Shmuel tells him that they are forced to wear them, Bruno thinks,
"....he did like stripes and he felt increasingly fed up that he had to wear trousers and shirts and ties and shoes that were too tight for him when Shmuel and his friends got to wear striped pajamas all day long." (pg 151-152)
This foreshadows Bruno's wearing of the stripes at the end of the book.
A foreshadowing event that takes place is when they shave Bruno's head because of lice. If his head had not been shaved, he would have been noticed by the soldiers and not included in the final walk or gassing. All of the prisoners had shaved heads, so his shaved head helped him to blend in with the crowd.
"When he saw himself in the mirror Bruno couldn't help but think how much like Shmuel he looked now, and he wondered whether all the people on that side of the fence had lice as well and that was why all theyr heads were shaved too." (pg 185)
Shmuel doesn't show up at their meeting place for a couple of days, and Bruno finds out that Shmuel's father is missing. He says,
"He was here on Monday and then he went to work duty with some other men and none of them have come back." (pg 194)
This foreshadows the walk to the gas chamber that Bruno makes with Shmuel and the other prisoners.
Bruno is being sent back home to Berlin. He says goodbye to Shmuel, but he says,
"....if I had a pair of striped pajamas too, then I could come over on a visit and no one would be any the wiser." (pg 198)
At this point in time, it strongly foreshadows what is going to happen to the boys.