Looking for John and Elizabeth Martin from Missouri

I think I Found John and Elizabeth Martin--Missouri to Arkansas
1870 Arkansas Census for John and Elizabeth Martin:
John age 55 Elizabeth age 53
(1)Wm age 18 (2)GW age 17(3)Darthula age 15(4)Armantha age 15
G W Martin is my ggrandfather and I found where he was born in Howell County Missouri but the County changed to Oregon County.

We found GW and his family in Clay County ,Chalkbluff,Arkansas
1880 Census
G W Martin bn Mo-1852 father KY mother GA
Amandy (BRYANT)Martin bn AR --1854 father bn IL mother bn IL
Lucy J bn AR --1875
John L bn AR--1878
Lucy J Martin married John Herren
Alfred,Wilbern and Willis are their children listed in 1900 census
John L Martin married Ida Sedrick
We think Amandy's last name was BRYANT