Probably #2122 in Sequatchie County Tennessee, 1870, born 1811-12:
"United States Census, 1870," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MD89-N25 : 12 April 2016), Sam Roberson, Tennessee, United States; citing p. 2, family 15, NARA microfilm publication M593 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 553,058.
"United States Census, 1860", database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M8YQ-K64 : 12 December 2017), Saml W Roberson, 1860.
"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MCD7-6LJ : 12 April 2016), Saml W Robinson, Bledsoe county, Bledsoe, Tennessee, United States; citing family 65, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).
Wife Eliza consistent in all three records, middle initial W in two out of three. FindAGrave gives wife Eliza, and her inscription looks like it's carved on another face of the same monument. If these three in Tennessee are all the same person, then
Malinda's husband (Roberson-2303) in Missouri in 1850, is definitely a different man:
"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MDZH-KD9 : 12 April 2016), Samiel M Roberson, Burbois, Gasconade, Missouri, United States; citing family 65, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.)
Here they are in Arkansas in 1860. Sam has a different birthplace, but wife and three children match the 1850 entry:
"United States Census, 1860", database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M87T-F61 : 13 December 2017), Saml M Roberson, 1860.