By Dorothea Shefer-Vanson Dorothea Shefer-Vanson MEVASSERET ZION, Israel — My connection with the Theresienstadt concentration camp, or ghetto, is based on the fact that the grandmother I never knew, Regina van Son, was deported there from her home-city of Hamburg in 1942, and perished there a few months later. I have maintained my late father’s subscription to the Theresienstadt memorial museum in Kibbutz Givat Chaim Ihud, though have not visited the place for several years. My interest has focused primarily on the artistic and musical activities that were held in the camp under Nazi rule, an…