Surname Saturday~Graves

Sarah Jane Graves is my 2nd Great Grandmother. She married William A. Purvis sometime before 1860. Sarah and William A. were living as a couple in 1860  Anson County. My Great Grandfather, their only child had not yet been born or conceived.
 
1860 CENSUS: Morven, Anson County, North Carolina; Roll: M653_887;  Image: 160; Family History Library Film: 803887; Page: 300; Line 34, Dwelling 1238, Family 1188; William A. PURVIS, age 34, Shoemaker, born in NC; Sarah PURVIS, female, age 26, born in SC; Joseph WHITE, age 33, Cooper, born in NC and Laura WHITE, age 30, born in NC. ¹

Sarah first appeared in the 1850 Chesterfield County Census as a 16 year old female in the household of Mary Graves, age 55, born in SC.
 
1850 CENSUS: Chesterfield County, South Carolina, Roll: M432_851; Image: 216, Film #0444814, Page 106A, Line 8, Dwelling 110, Family 110; Mary GRAVES, age 55, born in SC; David W. GRAVES, age 32, Tailor, born in SC; Sarah J. GRAVES, age 16, born in SC and Thomas GRAVES, age 14, born in SC. ²

The composition of this household is:
Mary Graves, age 55, born in SC  (Born 1795)
David W. Graves, male, age 32 (born 1818)
Sarah J. Graves, female, age 16 (born 1834)
[William] Thomas Graves, male, age 14 (born 1836)

I have studied, pondered, agonized and struggled over this family composition for many years with one thought in mind – Who are the parents of Sarah J.. Graves?.

Is this Grandma Mary Graves with her son David W and two grand children?
or
Is Mary the Mother of the the three living with her?

Another cog in this conundrum is the correct age of David W. Graves. His tombstone in the Old St. Mary’s Presbyterian Church shows that he was born 22 January 1812. If this date is correct and if Mary was also born as stated in 1795 then Mary would be 17 years old when her son David W. Graves was born.³

My thoughts are that Mary is Mother of David W. Graves and Sarah J. and William Thomas are her grandchildren. I also believed that David W. Graves is the father of Sarah J. and William Thomas Graves. Now I just need a way to proved or disproved this information. 

After the death of Mary Graves, David W. Graves married Mary Ann Gulledge about 1872. To this union 5 children were born 2 sons and 3 daughters.  David reported his age as 42 in 1860 and age 55 in 1880.

What do you think with the facts as presented here: Was David previously married and the Father of Sarah Jane and William Thomas Graves or is there inadequate evidence to draw a conclusion?





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[1] 1850 U. S. Census, Chesterfield County, South Carolina, population schedule, Chesterfield County, South Carolina, Page 106A, Line 8, Dwelling 110, Family 110, Household of Mary GRAVES; digital images, Ancestry.com (http://www.ancestry.com : viewed 20 November 2011); citing National Archives Microfilm M432 Roll 851.
[2] 1860 U. S. Census, Anson County, North Carolina, population schedule, Morven, Anson County, North Carolina, enumeration district (ED) No ED, page 300, line 34, Dwelling 1238, Family 1188, Household of William A. Purvis; online database, Ancestry.com (http://www.ancestry.com : viewed 1976); citing National Archives Microfilm Publication M653, Roll 887.
[3] Find A Grave, Inc., Find A Grave, digital image, (http://www.findagrave.com : Accessed on 1 January 2008); Headstone for David W. Graves; (22 January 1812–21 November 1898); Records of the Saint Mary's Presbyterian Church Cemetery (old); Patrick, Chesterfield County, South Carolina, USA.