My ancestors Jens Jensen and Kari Jacobsdatter emigrated to the united States from Norway with their family in 1861. They arrived in Quebec and traveled by rail to LaCrosse, WI and settled in Coon Valley near Chaseburg on the Elstad farm.
In the 1870 Census I found Jens listed as John Johnson, but with a new wife Ann Dardun. Children James 23, John 21, Edward 19, Mathias 17, Christian 12, Melvin 4, along with Edward 26 and Jane 14.
An older daughter is no longer at home Marit 25.
Also other children are listed in Obits Clara, who married Anton Peterson, also Mrs Thompson and Mrs Louis Elstad still living in 1912.
Marit was born in Oier, Oppland, Norway
By the time of their death, many of the childred listed Elstad as their surname.
Jens and Kari were married in 1843 in Oier.
they lived on the Elstad farm also in Oier, Oppland.
I can't determine what happened to the mother, Kari Jakobdatter/Jensen/Elstad/ from Oier, Oppland, Norway.
John and James were born in Gulbrandsdalen,
Are any of these in your book?