This is the only William Mobley living in Marshall County, Mississippi in 1860, therefore, I am assuming he is the one. The 1850 census for the same couple, and their marriage record is also pasted below. I think that their daughter Carrie married the grandson of the William H. Hall you have mentioned, but I am not sure. There is most assuredly a connection. I am sorry but I do not have time to work on this right now, perhaps in a few days. I will get back to you.
With kind regards----

Name: Wm Mobley
Age: 30
Birth Year: abt 1830
Birth Place: Mississippi
Home in 1860: Marshall, Mississippi
Post Office: Wall Hill
Household Members:
Name....................Age
Wm Mobley.............30
M Mobley................30
Mary Mobley...........10
Flora Mobley............8
Emma Mobley..........6
Josephine Mobley.....1

Year: 1860; Census Place: Marshall, Mississippi; Roll: M653_587; Page: 18; Image: 22; Family History Library Film: 803587
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Name: Wm C Mobley
Age: 20
Birth Year: abt 1830
Birthplace: Alabama
Home in 1850: Southern Division, Marshall, Mississippi, USA
Household Members:
Name......................Age
Wm C Mobley............20
Minerva J Mobley.......20

Year: 1850; Census Place: Southern Division, Marshall, Mississippi; Roll: M432_377; Page: 226A; Image: 40
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Marriage Record:

Groom Name: William Mobley
Bride Name: Manerva Jane Byers
Marriage Date: 7 Sep 1848
County: Marshall
State: Mississippi

Source Information
Ancestry.com. Mississippi Marriages, 1826-50 [database on-line]. Provo, UT, USA: Ancestry.com Operations Inc, 1999.
Original data: Dodd, Jordan R, et. al.. Early American Marriages: Mississippi.
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