Bruno's grandmother disagrees with the views of the Nazis. How does she stand up for her beliefs?

The grandmother's primary source of resistance is
questioning her son's beliefs and her son's value system.  Outside of this, there is
little to show that her standing up for her beliefs exists outside of the realm of the
personal.  She questions her son as to why he embraces the Nazi philosophy.  She does
this by openly questioning him, and also insisting that the values with which she and
her husband taught to Bruno are antithetical to what the Nazis believe.  While others
around her are impressed with her son, she is not and she speaks her mind about it. She
questions him about why he wants to "dress up" while "not caring .... what it stands
for."  Bruno's grandmother represents the few who had the courage to speak out against
the Nazis when it would come at great cost to them.  While others attempt to silence
her, such as her husband, she does not stop speaking what she considers to to be the
truth.  She does not recant or back down from her statements.  In this, she stands up
for her beliefs, even if it means openly questioning her son's
status.