Hi Elaine!
I am so excited to see your posting as I have been working on this Wallace family for some time. I hadn't seen your post until today. With Donna doing her travel research and several others of us online, I think we just may have the details starting to come together for certain. I am a descendant of Jonathan Wallace, who is my GGG grandfather.
I show in my files that Joshua S. was married to Elizabeth Bryan, daughter of Mary Bryan of VA (source probably from info I deduced from the 1860 census and the FamilySearch site.)
Children of JOSHUA WALLACE and ELIZABETH BRYAN are:
i. JOSHUA F.4 WALLACE, b. 1857, Warren Co., IA; d. Abt. 1866, Warren Co., IA.

More About JOSHUA F. WALLACE:
Burial: Wallace Cem, Wick Twp., Warren Co., IA

ii. JOHN B. WALLACE, b. August 1859, Warren Co., IA.
iii. ROBERT M. WALLACE, b. 1862, Warren Co., IA.
iv. ALBERT WALLACE, b. November 05, 1869, Warren Co., IA; d. October 11, 1870, Warren Co., IA.

More About ALBERT WALLACE:
Burial: Wallace Cem, Wick Twp., Warren Co., IA

Here is some census info I've gathered:
Census Records:
1850 Harrison Twp. Fayette Co., IN Census
Joshua Wallace, 69. b. DE, Farmer
Deborah Wallace, 29, b. IN
William Wallace, 25, b. IN
Joshua Wallace, Jr., 21. b. IA (I am confused about the birthplace of these three following children, but assume this is your Joshua S. and that the birthplace is possibly an error)
Martha Ann Wallace,18, b. IA
James Wallace, 16, b. IA
________________________________________

1850 Rush Co, Posey Twp., IN
WALLACE 411B-572A
Jonathan Wallace, 31, Farmer, b. OH
Mary E, 34, b. PA
Amelia, 5, b. IN
Amon, 3, b, IN
Elizabeth R. J., 10/12 b. IN
Henry J. Moore, 9, b. IN
Thomas Marlin, 13, b. OH

Probably went to IA in 1854

CENSUS YR: 1860 STATE: Iowa COUNTY: WARREN DIVISION: Jefferson Township REEL NO: M653-341 PAGE NO: 141 July 9, 1860
REFERENCE: Enumerated on the 7th day of July 1860 by A. R. Haynes
35 1006 961 Wallace Johnathan 40 M Farmer 3,500 1,000 OH
36 1006 961 Wallace Mary E. 44 F Penna.
37 1006 961 Moore Henry J. 20 M Ind. X
38 1006 961 Wallace Amelia S. 14 F Ind.
39 1006 961 Wallace Amon L. 12 M Ind.
40 1006 961 Wallace Rebecca E. C. 9 F Ind. X

24 1011 966 Wallace John S. 37 M Farmer 4,000 1,500 Ind.
25 1011 966 Wallace Julia Ann 35 F OH
26 1011 966 Wallace Jane 15 F Ind.
27 1011 966 Wallace Sophia 14 F Ind.
28 1011 966 Wallace John T. 13 M Ind.
29 1011 966 Wallace William A. 11 M Iowa
30 1011 966 Wallace Joshua 9 M Iowa
31 1011 966 Wallace Frances 7 F Iowa
32 1011 966 Wallace Emeretta 4 F Iowa


23 1018 973 Bilby Jos. N. 25 M Lawyer 240 Ind.
24 1018 973 Bilby Margt. E. 25 F OH
25 1018 973 Bilby Stephen 4 M Ind.
26 1018 973 Bilby Francis M. 2 M Ind.
27 1018 973 Bilby Mary Alice 1 F Ind.
28 1018 973 Bilby Julia Ann 7/12 F Iowa

29 1019 974 Wallace Joshua 70 M Farmer 3,000 1,000 Del.
30 1019 974 Wallace Rebecca 50 F OH

31 1020 975 Wallace Joshua S. 29 M 1,000 500 Ind. (I am assuming this is your ancestor)
32 1020 975 Wallace Elizabeth 23 F Ky.
33 1020 975 Wallace Joshua F. 3 M Iowa
34 1020 975 Wallace Jno. B. 10/12 M Iowa
35 1020 975 Bryan Mary 57 F 600 150 Va.
36 1020 975 Wallace William 34 M 6,000 Ind.


I would love to know more about your research too, especially info regarding when and where the Wallace family lived in OH and and info surrounding the time frame your familycame to CA. I live in CA currently and as far as I've gleaned, my great grandmother, Jessie Carrie May Wallace Eames, grandaughter of Jonathan, came to Fillmore, Ventura Co., CA around 1929.
Looking forward to hearing from you.
Sincerely,
Leanne Wiese