My great grandparents also came from the Posen area of Bromberg, Nakel,Germany now Poland.
My mothers mothers parents were Carl and Rosalie boettcher(or Bottcher) Carl came from Crone,BRomberg,Posen. His wife was Rosalie Kannenberg whose parents were Michael and Catherine (Frase) Kannenberg. They came from Witowolo,Posen.
Rosalie had a sister Caroline and 2 brothers Carl Ludwig and Eduard George.
Could they be related to you?
If they are I would like to hear what info you may have regarding the family. PAt