Mom's Memoirs:

The doctor advised my mother to get pregnant again as soon as possible, which she did. When my grandmother heard of the new pregnancy she insisted that my parents come to Berlin “where all the good doctors are” and my parents packed up and went. A mistake that was to change their lives forever. My father could not find an academic job, neither of the families were in a position to render financial assistance, the early 20’s in Germany were tumultuous, the saved Swiss francs had been converted into German marks which soon became worthless. A return to Switzerland became impossible, and so they were stuck. My father had to take an industrial job which he hated, and he was never able to get out of it. He had a tiny lab where he experimented with cosmetic product at the side, but never “made” it, stayed in detergents for the rest of his life (also later on in England).

So a few months after they came to Berlin I was born in a clinic, don’t know how long the stay was there in those days, and then I came home to a furnished apartment in the “Tiergarten Viertel”, an area in central Berlin close to a very nice large Park, called Tiergarten (much like Central Park in New York) .

...

As you probably all know I was born in Berlin, unfortunately. By German law, a person does not acquire citizenship by being born in the country, but has the nationality of the parents at the time of birth; that made me Polish. After WWI when Poland was created (or recreated), put together from the German/Austrian/Russian parts, people born in that geographic region could chose what they wanted to be, and my parents opted for Poland,

Notes:

Note the parenthetical "(Jeanne)" on her birth certificate, which then became her default middle name. Just supposed to be the French version of her name. Also, interesting that nothing on the birth certificate seems to note their Polish nationality. [Also, interesting that here is one instance where Mom and Dad actually translated German originals.]