This is Mary Jane Byers Mobley as she appears on the 1880 census. Her husband apparently died between 1876 (birth year of youngest child) and June 27, 1880 (date on the census).

Name: W.J. Mobley
[M.J. Mobley]
Age: 48
Birth Year: abt 1832
Birthplace: Tennessee
Home in 1880: Armstead, Marshall, Mississippi
Gender: Female
Relation to Head of House: Self (Head)
Marital Status: Widowed
Father's Birthplace: North Carolina
Mother's Birthplace: North Carolina
Occupation: Farmer
Household Members:
Name Age
W.J. Mobley.......48……female..........born Tennessee
Emma Mobley....24……daughter......all children born Mississippi
Lucy Mobley.......19…..daughter
W.M. Mobley......18…..son
C.E. Mobley.......10……daughter
U.J. Mobley.........4……..son

Year: 1880; Census Place: Armstead, Marshall, Mississippi; Roll: 657; Family History Film: 1254657; Page: 535B; Enumeration District: 118; Image: 0411
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This is the same family in 1900:

Name: Minerva J Mobley
Age: 70
Birth Date: May 1830
Birthplace: Tennessee
Home in 1900: Holly Springs, Marshall, Mississippi
Relation to Head of House: Head
Marital Status: Widowed
Father's Birthplace: North Carolina
Mother's Birthplace: North Carolina
Mother: number of living children: 4
Mother: How many children: 9
Household Members:
Name Age
Minerva J Mobley.......70.....head.................seamstress.......widowed.....born Tenn. May 1830
Emma Mccarson........38.....daughter...........coat maker.......widowed.....born Miss. Dec. 1861
Aubrey Mccarson.......22.....grandson...........stone cutter......single........born Miss. Aug. 1877
Carrie Hall ...............28.....daughter...........seamstress........widowed....born Tenn. Jan. 1872
Lillian Hall..................5.....granddaughter...seamstress........single.......born Miss. Aug. 1894
Tom Brinkley............26.....boarder

Year: 1900; Census Place: Holly Springs, Marshall, Mississippi; Roll: 820; Page: 9B; Enumeration District: 0060; FHL microfilm: 1240820
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I could not locate this family on the 1870 census.

I also found them on the 1850 and 1860 census, and if you would like the information I would be happy to provide.

Best regards---