Kirk, I have seen Johann's grave and his name appears as John Frankenstein.He is buried in Brookside Cemetary near Brookside, WI.As best we could read the cracked gravestone, it says "den 10 ???? 1875". The "seven" in the 1875 is not clear however.The rest of the inscription is"After 59 yahre und 3 monate".We did not see Carolina's grave there. Their daughter Caroline was married to a Schroeder who lived in the Brookside area north of Green Bay.Are you a relative?