Bob's advice (as always!) to start at the beginning is very sound - have no idea exactly why but it triggered me to look on surname boards for Werchan, an unusual name. The Werchans seem to have come from Germany (Posen area) but it clearly states Mathilde came from "Austria". Although no one seems to have posted for a couple of years someone who goes as "?miller" has been asking/offering advice on the family and amongst a lot of other stuff has birth and death details for all eight of Matilda Schaefer and Ferdinand(?) Werchan's children. If you haven't seen this it might be worth taking a look and trying to make contact. Obviously if you have, don't waste any time. Good luck with the search.