What is Mother's reaction when she sees Gretel's room decorated with Nazi posters?

Mother's reaction clearly demonstrates fear. As an adult
and with her husband the commandant of a camp, she knows what Hitler and the Nazi party
really stand for and these are not values she wants her twelve year old daughter to
embody. It's also a realisation of just how powerful the Nazi party have become, that
they have been able to influence children through the Hitler Youth and through
education. On some level, Mother is also angry. Isolated from most of the world, Gretel
and Bruno only have limited influences and Mother observes that the indoctrination of
the Nazi agenda and ideas comes from the children's tutor.