Judging by their treatment of Maria, Bruno and Gretel are certainly different: Gretel seems to feed off her father's new superiority and harshness, while Bruno is more sensitive like his mother. Unlike Gretel, Bruno strives to understand more deeply his surroundings and new situation, and as he talks with Maria, he learns of her past.
In Chapter 6, Bruno lies on his bed, looking at the ceiling, bemoaning the poor condition of the house in comparison to his Berlin home. Maria enters with folded laundry and he says,
"I expect you're as unhappy about the new arrangement as I am...Everything here. It's awful, isn't it? Don't you hate it, too?"
As a servant, Maria knows not to offer her opinion. Instead, she asks, "Don't you like it here?" Bruno replies that it is "awful"; there is no one with whom he can play, and there is nothing to do. Wistfully, Maria remarks on the lovely garden and other amenities back in Berlin. Bruno realizes that she would like to say more, but she does not. Continuing with his complaining, he says, "Stupid Father." Maria is horrified by this comment, and tells Bruno he must never say such a thing. "Your father's a good man," she tells Bruno, explaining that her mother was a dressmaker for Bruno's grandmother, who was a performer. Later on, when her mother was ill, Bruno's father paid for her care and took Maria into his household as a servant so that she would not be destitute. Maria tells Bruno not to disparage his father around her, yet she does remark, "He has a lot of kindness in his soul, truly he does, which makes me wonder...." Suddenly, though, she stops herself.
Maria and Bruno are then startled by a door slamming shut, followed by thundering steps down the stairs. Gretel barges in and says, "What's going on?" "Narrowing her eyes suspiciously," she orders Maria to run her bath. When Bruno tells her she can do this herself, Gretel tells her brother Maria is the maid and she is there to wait on them. Bruno disagrees, but Gretel orders Maria to "not be long" because
...unlike Bruno she never stopped to think about the fact that Maria was a person with feelings, just like her.
Gretel derives an attitude of power from her father's new position. Unlike Bruno, she is self-centered and not concerned with the feelings of others. Gretel exhibits the innate feelings of superiority that her father and other Nazis felt, but Bruno does not exhibit such traits; instead, he is compassionate.