A secondary source has Patience dying ca. 1812 in Huntingdon Co., PA, a datum apparently intended to support James's departure from Vermont and his supposed second marriage to Sophia CORBIN (whose supposed siblings lived in Huntingdon Co., PA) and the birth of son, James, in Virginia.  But Patience is clearly still alive in 1850 (see 1850 Census below), so these must be two different James SIASes [see family group sheet of James & Sophia (CORBIN) SIAS].  Also casting doubt on the identity of our subjects as the parents of the James SIAS in West Virginia is the 1880 Census, in which this James states his father was born in Virginia and his mother in North Carolina, which not only removes James & Patience from the realm of possibility, but also casts doubt on the supposed origins of James & Sophia.

There is also the possibility that Patience died and James remarried — another Patience.  The Patience in 1850 is 13 years younger than James.  And bearing children from 1805-1837/8 is an extraordinary period of fecundity, though not impossible if Patience was very young when married, which she would have been as she was 13 years younger than James.  However, given the apparent age difference between James and Patience and the extraordinarily long span of child births, the best case scenario is that John had a prior wife.  So, how dependable is the marriage date to Patience?  All I have is a secondary source, and we've seen how unreliable the early work on this family has been.

.  Nancy SIAS, b. 27 Jan 1805 
?  Sarah "Sally" SIAS, b. 1805/6 
.  Patience SIAS, b. ca. 1812
?  James William SYAS, b. ca. 1816 
?  Ezra SIAS, b. 1816/17 
.  Abigail SIAS, b. 1830/1
.  Serepta SIAS, b. 1832/3
.  Lucretia SIAS, b. 1837/8

With at most only four known children born between 1805 and 1830/1, there must be many more children of which we are unaware (the numerical data from the pre-1850 censuses should at least give us the numbers and genders). 

There is a Sarah SIAS said to have married George W. SMITH and to be the daughter of Charles SIAS, Sr., (i.e., to be sister of our subject, James SIAS), but she is too young to be Charles, Sr.'s daughter, yet too old to be the daughter of Charles SIAS, Jr., who wasn't married until 1808.  George and Sarah are living three doors down from James and Patience (DWIER) SIAS in the 1850 Census, and I think it highly likely she is their daughter.  Supporting this connection even more strongly is the further fact that George & Sally are on the same page with James & Patience in the 1840 census of Coventry — and James & Patience are the only SIASes in Coventry in 1840.

A secondary source has Patience born in Huntingdon Co., PA, which cannot be correct, for reasons given above. 

1.  LDS.  Family Search: Internet Genealogy Service:  AF - Ancestral File (online at FamilySearch.org).

James SIAS Birth: 18 May 1778, West Derby, Orleans, Vt Death: 23 Mar 1835 Father: Charles L. SIAS; Mother: Jane McCRILLIS Source: patron submission

If this source is correct about the years of James's death (big if), then it's "back to the drawing board."

2.  LDS.  Family Search: Internet Genealogy Service: International Genealogical Index (IGI).

Nancy SIAS Birth: 27 Jan 1805, Of Derby, Orleans, Vermont Father: James SIAS; Mother: Patience DWIER Source: patron submission

3.  1810 Census Index/Images (this image appears to be missing at Ancestry.com; online at Genealogy.com, but mis-grouped as Image #1 of 1 of Duncansboro; extracted by Diana Gale Matthiesen):¤•

1810

VT

Orleans Co.

Derby

p. 449A/190

Ln. 9

James Sias

10010-30010-00

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	9 or under	1800-1810	= Son A
1 male	26-44	1765-1784	= James (b. 1778)
3 females	9 or under	1800-1810	= Daughter C = Daughter B = Daughter A
1 female	26-44	1765-1784	= Patience?

4.  Census Index:  U.S. Selected Counties, 1820 (Broderbund CD-314):  not found.

5.  Census Index:  U.S. Selected Counties, 1830 (Broderbund CD-315):

1830

Sias, James

VT

Orleans Co.

Derby

p. 199

Son-in-law George W. SMITH is also in Derby, but on p. 201.

6.  Census Index:  U.S. Selected Counties, 1840 (Broderbund CD-316):

1840

Sias, James

VT

Orleans Co.

Coventry

p. 359

They are the only SIASes in Coventry.  On the same census page with probable son-in-law, George W. SMITH.

7.  1850 Census Index/Microfilm (online at GenealogyLibrary.com):  Newport, Orleans Co., VT, p. 134A, 88/88, enumerated 29 July 1850 (extracted by Diana Gale Matthiesen):

James Sias	72	M	Farmer	400	NH
Patience	59	F			NH
Abigil	19	F			Vt
Lucretia	12	F			Vt
Serepta	17	F			Vt

At first, I thought Patience must be fibbing about her age because being 59 in 1850 makes her only 12 or 13 years old when she married in 1803.  But the birth of Lucretia in 1837/8 can only be explained by her mother's youth as a bride — and marriages this young did take place in New England, not just Appalachia.  Or is it the unlikely scenario that the first Patience died and that James married again — another Patience?

8.  Census Index:  U.S. Selected Counties, 1860 (Broderbund CD-318):  not found, but he is likely living with one of his children, especially if Patience had already died (n.b., on this CD, many SIASes were misread and indexed as LIAS).

9.  Descendants of John Sias Sr. by Garey L. Marshall.

10.  Broderbund.  World Family Trees.  Vol. 1, Pedigree #4903.