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From various records including census etc. It appears that August was the son of Christian John and Gustena (Justina) Wagoner and his spouse was Christina Knebel, b. Ger 1863, dau of Unk and Henrietta Knebel. By plugging in siblings names etc you may find much more. Gustena apparently died prior to the 1870 census.
Texas, Deaths
https://familysearch.org/pal:/MM9.3.1/TH-1942-25170-101129-89?cc=1983324&wc=MMTK-9FV:n1968571505
August Wagner
Address: RFD #2, Fayetteville, Fayette TX
Death 31 May 1941 Ellinger, Fayette, TX
Death age 78 yrs 3 mos 5 days
Male Married
birth 26 Feb 1863 Shelby, TX
father John Wagner Birthplace Europe
mother Unk
Informant Fred Wagner, Rte 2, Fayetteville
Burial June2, 1941 Haw Creek Near RoundTop.
certificate number: 22367
https://familysearch.org/pal:/MM9.3.1/TH-266-11603-110822-98?cc=1320964&wc=13012895
Christine Wagener
death 06 Oct 1954 Rural, Fayette, TX
Female White Widow
death age: 91 years 17 days
birth 19 Sep 1863 Germany
father unk mother unk
Informant Fred Wagoner
residence: Fayetteville, Fayette, TX
cemetery: Maw Creek
burial date: 08 Oct 1954 Fayetteville, TX
1860 Census Fayette, TX page: 31 family number: 251
Chistian Wagoner 35 yrs abt 1825 Prussia
Gustena Wagoner 36 yrs abt 1824 Prussia
Gustena Wagoner 10 ys abt 1850 Prussia
William Wagoner 8 yrs 1852 TX
Christena Wagoner 6 yrs abt 1854 TX
Henry Wagoner 4 yrs abt 1856 TX
Christian Wagoner 1 abt 1859 TX
US Census, 1870 Precinct 3 Fayette, TX
Christ. Wagner M 57y Prussia
Justine Wagner F 21y Prussia
Wm Wagner M 18y Prussia
Christine Wagner F 16y Prussia
Henry Wagner M 14y Prussia
Christian Wagner M 12y Prussia
Emma Wagner F 9y Prussia
August Wagner M 6y Prussia
Lina Wagner F 4y Prussia
US Census, 1880 Precinct 2 And 3, Fayette, TX
self Christian Wagener M 66 GER abt 1814 widowed
son William Wagener M 28 TX
son Christian Wagener M 21 TX
son August Wagener M 17 TX
US Census ED 35 Justice Precinct 3 Warrington & Haw Creek towns, Fayette, TX
https://familysearch.org/pal:/MM9.1.1/M3GQ-HCJ
head August Wagner M 37 Feb 1863 TX/GER/GER married abt 1884
wife Christena Wagner F 37 Sept 1863 GER immig 1866 9 children 7 living
son Fridolen Wagner M 15 Texas
dau Lillie Wagner F 13 Texas
dau Edna Wagner F 11 Texas
son Perry Wagner M 7 Texas
dau Louise Wagner F 5 Texas
dau Elsia Wagner F 2 Texas
dau Wagner F 0 Texas
mother-in-law Henrietta Knebel F 75 Sept 1825 GER widow immig 1866 7 children 5 living
US Census, 1880 Precinct 2, Fayette, TX
self Henrietta Knebel F 53 GER widow
son Henry Knebel M 22 GER
dau Mena Knebel F 20 GER
dau Christiana Knebel F 17 GER
