Since posting this query just over a year ago, I have been able to discover the answers to my questions, and also to discover some living relatives on a branch of Luehr family tree.
John and Peter Luehr [Luhr] were brothers from the Dithmarschen in western Holstein. John's wife'd maiden name was Anna Margretha Groth, and she was also from Dithmarschen.
While Peter married and eventually moved his family to Iowa, John Luehr farmed and ran a brick making operation on the northwest side of New Holstein for several decades. He and Anna had four sons. The oldest, Johann or John, immigrated to America with them. Three sons followed including William Henry Luehr, my great-grandfather; Edward and Arthur.
William Henry Luehr married Clara Hachez, daughter of Ferdinand and Elise Boie Hachez of New Holstein. Ferdinand and Elise each came to New Holstein with their parents in the early days of the village.
I have collected considerable information on the Boie, Hachez and Luehr families of New Holstein and descendants, some who remained there and others who sought new opportunities, either elsewhere in the Midwest or in the Pacific Northwest.
I would enjoy corresponding with anyone interested in these three families or in early New Holstein history.