Having a birth parent that was an immigrant recent to the US or who came out of Europe during WWII can complicate the results of DNA testing and building reliable family trees. More than ever it makes it overly complex to attain records to backup the theoretical trees taken from Ancestry.com hints.
Immigrants coming out of WWII Europe may have been wiped out or scattered throughout the region because of the devastation that occurred during that time. Add upon that the potential close-knit communities where cousins may have intermarried; even if they were distant cousins, and it makes DNA testing altogether unreliable.
I have built four theoretical family trees for one of my clients. They have only seen one of them, because I felt it was the closest to reality. However, I have genetic ancestors now stepping forward to wreck those trees based on their own family knowledge of their ancestors. I welcome their assistance; it is just frustrating to face so many obstacles.
The trust required to work with some of these families who have the knowledge is also daunting. Most prefer to keep their information secret. Especially if you are not a part of their family, so approaching them requires delicacy and promises. All of which I intend to keep, it is just not like grinding through hints and documentation to build out trees. Each step requires extra research. Hints become all but worthless.
Even if you find these people in census polls their names have been so mangled or Anglo sized in such a way that one cannot rely on them unless several family members with unique names seem to align. One misstep and a family tree can go off into the wild blue yonder. Believe me, you don’t want to find out after five hundred people into a tree that your twentieth step in was incorrect.
Once the language and names cross the border back into the eighteen hundreds everything starts to turn to mush, unless you have a direct connection to a family who had a reputation of keeping great records of their ancestors. In the past year I have only seen it happen once.
Some of the links I have on the website attempt to work with cultural, religious, or regional genealogy that is specific to the birth parents of adoptees who require additional understanding about their families. It can easily move someone from a relatively straightforward kind of research to a much more culturally diverse background specific to the area his or her families originated from.
There have been times I have seen individuals requiring a genealogist with the ability to read a foreign language just to investigate their immigrant ancestors families.