Terry Lee, I believe Mary Joyce Murray would be listed in the 1880 US Federal Census for St Croix County, WI in James Murray household.
That Census year of 1880 probably has a lot of Genealogical Information on her family.
Email me at
hnasep@sbcglobal.net and I will send you a couple of Genealogy charts/forms.
Jack
Manitowoc, WI