A client sent me a translated marriage record, identifying a nephew as a witness. She had searched for the nephew but could not find any siblings of the person of interest. When I looked at the original marriage record, the witness was called a neef, a term that is used for both nephew and cousin. As it turned out, the witness was a first cousin rather than a nephew.
Are you sure your translations are accurate?
When you have a brick wall, always go back to the original records to make sure you did not make any incorrect assumptions. If you need help finding the record, or reading or understanding what it says, I can help you.