With your help the question was solved. Her son Leo Leib ROSNER immigrated to the US in 1947 and Ancestry has the details of his parents. Leo was born in 1908 in Berlin. His mother
was Dwora BALSAM and she was born in Tarnow. It seems that the family went back to Poland after 1933. JRI-PL has her birth record and interestingly her father's given name was Arie
which means lion in Hebrew. Her maternal grandfather was called Leib. Yad Vashem has several PoTs filled by different people called Leo Rosner which caused some initial confusion.
Thank You all.