The father of Goslar was hoofd of the personal service of the Pruisische ministerie of Buitenlandse Zaken. Na de power overname by de nazi’s emigreerde de family naar Amsterdam, waar Goslar Anne Frank leerde know. Goslar, born in Germany, same with Anne Frank at school. Anne Frank noemde haar also wel Hanneli. The two lost elkaar uit het oog toen the Frank family in 1942 most onderduiken.
In June 1943, Goslar was deported to the concentration camp of Bergen-Belsen. Then ontmoette zij Anne Frank nog een keer, in February 1945, vlak voordat Anne Frank overleed. Goslar overleefde de oorlog uiteindelijk. Zij was later verplegständigen en trouwde with Walter Pinchas-Pick. He had a couple of three children and eleven small children in a sea of twin eight small children.
The Dutch film ‘Mijn Beste vriendin Anne Frank’, which is based on Netflix, is based on the state of affairs that Goslar has on the Tweede Wereldoorlog heeft verteld. Goslar also appears in the document ‘De Last Zeven Maanden van Anne Frank’, made by the Dutch document maker Willy Lindwer. The documentaire has won an International Emmy Award.