I believe you are correct. My ggma was her sister, Theresia, (many spellings on this name) and they had several siblings. I see that you listed Yanski as a surname and I believe that was possibly their mother's maiden name, my gggma, I can't find any info on her at all except she was married to Charles Lehmann. I am also looking for the surname Zugmaier. John was my ggpa, Theresia's husband.