Yes, you had a half sister.
In norway she had one daughter, my friends mother.
So you have a niece in norway!
I do not know my friend in personal. I have just helped her this last year to find information about her grandmother.
We tried almost everything in our search, but no one could help us, neither the embassies, Red Cross or Salvation Army.
But thread by thread we found Sigrid Pauline's headstone in Germany. We are still working to find her descendants,we have heard she had two children in her marriage, but when you are looking for living persons it is a challenge to find anything.
I'll send you a personal message to get in contact.