In 1900 Nelson was living in Sheridan, Sheridan, Wyoming.
Nelson Mossberg, head, b. June 1870, Sweden, single, immigrated 1888, cook.
He married Jenny sometime after the 1900 and before the 1930 Censuses.
In 1930 they were living in Dry Creek, Arapahoe, Colorado.
Nels Mossberg, head, b. Sweden, 59, imm 1888, naturalized, general farmer.
Jenny, wife, b. Sweden, 54, imm 1910, nat, 54.
I couldn't find their death information.
In 1900 Ole was living in Sheridan, Sheridan, Wyoming.
Ole Mosbug b. Sweden, Aug 1867, single, ranch laborer.
He married Helga after the 1900 but before the 1910 Census.
In 1910 they were living in Sheridan.
Olaf Mossburg, head, b. Sweden, 41, marr 7 yrs, deputy sheriff county.
Helga, wife, b. Sweden, 30.
They had three boarders living in their house.
In 1920 they were living in Banner, Sheridan, Wyoming.
Ole Mossberg, head, b. Sweden, 52, imm 1889, nat, general farmer.
Helga M., wife, b. Sweden, 46, imm 1885, nat.
Carl Johnson, nephew, b. IL, 9.
In 1930 they were living in Sheridan Co., WY.
Olaf Mosberg, b. Sweden, 62, farmer grains & stock.
Helga M., b. Sweden, 57.
Carl A. L. Johnson, b. IL, 29 [assume he's the same nephew], farmer hay & grain.
I couldn't find their death info either. Successful Searching!