You are right, the problem is that there is an important link missing between the oldest Steinbrenner, Marta, born in 1905 and all the other Steinbrenner’s I can find. But for sure the Steinbrenner’s I have in my family were all born in Stefanow, but their parents could have moved to Stefanow from somewhere else.
I still have a Jan and Maria Steinbrenner nee Beger named in Marta's Death Certificate as Marta’s parents, but with no place and dates of birth or death I can’t connect them to anyone, yet.
The only solid information I have is of August Steinbrenner *24/06/1898 as his son Willi is still alive (in his late 80’s) He remembers my father as they were cousins, but nothing more.
Names and dates I have in my family are:
Alfred Steinbrenner *31/01/1926 in Stefanow +15/09/2001
Marta Steinbrenner *16/03/1905 in Stefanow +06/02/1951 in Stare Chrusty
I know that Alfred’s mother was named Marta (as I was named after her) and she was born in 1905 in Stefanow, so I hope I have found the death Certificate of the correct Marta as I assume that not too many Marta’s were born in 1905 in Stefanow.
Marta's siblings could have been:
Wilhelm Steinbrenner *24/07/1888 in? +?
Johann Steinbrenner *23/10/1884 in Stefanow +1955
August Steinbrenner *24/06/1898 in Stefanow +18/12/1966
I also know of Gerhard Steinbrenner DOB 29/12/1929 who died on 30/01/1976 and is buried in Portland Oregan. He was the son of August Steinbrenner and the brother of Willi (still alive). He was the only Steinbrenner I knew off, who went to USA, but he died unmarried without children.
So at this stage I am grateful for any Steinbrenner’s I can find in ‘Mittelpolen’. I am collecting everyone and hopefully one day I can find the missing link. So thank you very much for your help.