Just as a starting point, here's Annie and Joseph's marriage license. Annie Harper, of Harper's Place, Desha County, Arkansas:
"Arkansas, County Marriages, 1837-1957," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:NMNJ-9BM : 4 November 2017), Joseph Varden and Annie Harper, 25 Jan 1887; citing , Desha, Arkansas, United States, county offices, Arkansas; FHL microfilm 2,027,477.
Derius was married to a Martha E in 1880:
"United States Census, 1880," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MNW3-Z4N : 12 August 2017), Anna J Harper in household of Deriona M Harper, Jefferson, Desha, Arkansas, United States; citing enumeration district ED 77, sheet 303D, NARA microfilm publication T9 (Washington D.C.: National Archives and Records Administration, n.d.), roll 0043; FHL microfilm 1,254,043.
Here they are in 1870, without Martha E. No Malissa, either:
"United States Census, 1870," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MNCS-QG4 : 12 April 2016), Anna Harper in household of Darnas M Harper, Arkansas, United States; citing p. 17, family 188, NARA microfilm publication M593 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 545,551.