I just found your message from 2002 concerning the Grabow family from South Dakota being related to the Grabow of Renville County.
I am the G granddaughter of Fredrich H Grabow and all his descendents that you mentioned. Fredrich H Grabow's father's name was Gottfried Grabow. My understanding is that Gottfried had 2 other brothers in the Minnesota area (Gottlieb and Jacob) who came to MN earlier (1860's) and settled in and around Brown County (New Ulm/Sleepy Eye, Minnesota). e-mail me at: firstname.lastname@example.org