Who is maria in the boy in the striped pajamas?

Maria works for Bruno's family as the maid.
She has worked for the family since Bruno was three years old. As the maid, she is responsible for the upkeep of the family home. Maria also does the grocery shopping and sometimes takes Bruno to school.
When Bruno is unhappy at "Out-With," Maria tries to console him. However, Bruno will not be appeased. He contends that his father has made a mistake in moving the family away from Berlin. For her part, Maria is too indebted to Bruno's father to criticize her employer behind his back. As the other educator has already pointed out, Maria's mother worked for Bruno's grandmother as a dressmaker. Bruno's grandmother was a performer during her younger days, and Maria's mother followed her all over Germany.
After Bruno's grandmother retired, she gave Maria's mother a small pension. Not long after, Maria's mother succumbed to illness and died. Throughout the ordeal, Bruno's father supported Maria; he paid for her mother's medical care and later for funereal expenses. Then, Bruno's father brought Maria into the family home to work as a maid.
So, when Bruno confides his disappointment in his father to Maria, she refuses to sympathize with him. To Maria, Bruno's father is a good man. At least, that is what she will allow herself to say in public. Yet, Maria is obviously troubled that her employer has chosen to support Hitler's murderous policies.
Despite her reservations about Bruno's father, however, Maria is afraid to speak candidly. She tells Bruno that it is better to remain silent than to question his father. As an adult, Maria has probably seen how independence in any form is violently crushed. So, she advises Bruno to concentrate on his schoolwork and to do as his father says. To Maria, it is better to remain silent and stay safe than to speak up and possibly incur death for one's efforts.

The Boy in the Striped Pajamas is a book about a young boy and his family taking up residence near a concentration camp. The young boy, Bruno, develops a friendship with a Jewish boy named Shmuel, though he is naive to the fact that his new companion is suffering through life in a concentration camp.
Maria is Bruno's family maid and is considered a "minor" character in The Boy in the Striped Pajamas. Maria's mother worked as a dressmaker for Bruno's grandmother during her tour in Germany. The two women remained friends, even after Bruno's grandmother retired.
When Maria's mother fell ill, Bruno's father took care of the medical costs. When Maria's mother passed away, he also paid the expenses for the funeral and hired Maria as a maid. This act of generosity provided Maria with a job, food, and a home.