The second chapter begins with a conversation between the same two adults, who apparently approve of the way that Ender dealt with Stilson, comparing his actions to those of someone named Mazer Rackham. However, they are worried about Peter's reaction. Their concern, however, is tempered by the fact that they realize their job is not to make Ender happy but to save the world. The action returns to Ender's home, where his sister Valentine is comforting him over the loss of his monitor, although Ender does not seem to care. His brother Peter is angered by the fact that Ender had his monitor for longer than he did. Peter decides that he and Ender should play buggers and astronauts, a common children's game. However, Peter actually hurts Ender during the game, as he has in the past, treating his brother like a hated enemy. Even as Peter is preparing to do physical damage to him, Ender stops to think about what it really feels like to be a bugger, and what they think about humans.
Peter, a full four years older than Ender, remarks out loud that he could kill Ender by slowly crushing the air out of his lungs with his knee and how everyone would think it was an accident. Ender does not think Peter is serious but knows it is possible. Valentine talks Peter out of it by pointing out that if he wants to enter politics he cannot have anything that looks this bad in his past, and he relents, although he tells her never to stop watching Ender because someday he will kill him. Peter goes even further, telling Valentine that it will look like an accident and she will not want to blame him. But, Peter says, he will kill Ender eventually.
Then Peter laughs about it all, claiming he was just messing around. Ender's parents come home, with very little to say, and it is clear that Ender cannot relate at all to them, except that he knows how awkward he makes them feel, since he is a Third, and he hates that feeling. Finally, while Ender is lying in bed at night, Peter comes to him, and at first Ender fears for his life. However, Peter apologizes, claiming that Ender is his brother and he loves him. Later, after Peter falls asleep, Ender cries again.
Ender's story gets more complicated in the second chapter. Peter is revealed as a truly dangerous character. The disembodied voices' concern about how Ender will handle Peter is legitimate, for Peter appears at times to be evil incarnate. There are two key features to Peter's personality. He is capable of ruthlessly killing his own siblings. He is also a genius, and incredibly manipulative. Ender fears he has become cruel like Peter after beating Stilson, but it is unclear whether he can be as manipulative as his brother.
Peter's situation is both interesting and crucial. The comparison between the siblings is a constant theme throughout the book, and Ender cannot bear the thought that he and Peter might really be the same after all. There are two sides to this comparison. Saying that Ender is like Peter makes Ender appear bad, but it might also be that there is some good in Peter. Although it is not clear whether Ender believes him or not, Peter does apologize at the end of the chapter. Peter might truly be asking his brother to forgive him or it might be another attempt at manipulation. The point is not that one or the other possibility is correct, but rather that both are possible. Card sketches complex characters with real human traits, and they are not so easily classified. Furthermore, it may be that Peter himself is not always so sure of his emotions. The interplay between good and evil, and the fine line that separates them, is an important motif in Ender's Game. Even if he was acting for his own benefit, Peter's words comforted Ender, and he therefore would have accomplished good ends through evil means. On the other hand, when Ender beat up Stilson in the first chapter, his good intentions—he wanted only to protect himself—led to a bad outcome. Not only are good and evil hard to separate within a person, good and bad acts are not so easily distinguished.