Welcome to Just Answer and thanks for your question.
Do you know where in Schlesien she was born?
Who and when/where did she marry?
Where did she die?
Have you obtained her death certificate and marriage certificate?
I see. Were the children all named Hoetzel or Berger?
I've checked and the records are not available outside of the country. The birth, marriage, and death records have never been microfilmed by the LDS so that they can be accessed in the Family History Centers all over the world.
One has to write to the Civil Registry Office (Standesamt) in the city where the event occurred giving the name of the person and the date of birth/death, etc. They will write back detailing the cost (usually under $15).
Rathausplatz 1 85406 Zolling
Some records were also taken to Germany after WWII. They are now stored at the Standesamt I, Rückerstraße 9, D-10119 BERLIN, GERMANY.
You can also write to the Director of the Polish archives and they will forward your request to the appropriate place: Here is the contact information.
Naczelna Dyrekcja Archiwów Panstwowych ul. Dluga 6 00-950 Warszawa skr.poczt. 1005 Poland Fax: 48 22 831-75-63 E-mail:***@******.***