I am sure that he and Catherine Whitenack were married in warren county, ohio. They left there with 2 girls and had a son on the way to Missouri. I think his father was David Dunham. I hope some one can help me find a connection.
I found them in the 1880 census still in Ohio

FamilySearch database of the 1880 Census, Carondelet, St. Louis, MO, DUNHAM: Francis M., 46, OH OH OH; wf. Catherine, 39, OH NJ NJ; ch. b. OH: Belle I., 18; dau. S. E., 14; son b. IN, David, 12; ch. b. MO: Liew, 10; Lilly, 8; Frank, 6; Neal, 3.

Do you mean that you think these are parents of Francis Marion?

David, 72, OH NJ PA; wf. Mary, 66, OH IRE OH; Cincinnati, Ham., OH, 1880.

David is not listed as part of the family in the History of Warren Co., but it would seem likely that he could be connected further back. There is a David in Dunham Genealogy by Isaac Watson Dunham who was b. ca. 1770, m. Mary SHA[C]KERLY, went to Warren Co., OH, & had a son David, but recent DNA information shows that this is probably the SINGLETARY line who used the surname Dunham. [You need to check information from Dunham Genealogy. See RootsWeb Family Trees.]

USGenWeb > OH > Warren Co. > Beers' History of Warren County > Biographies: Edward Dunham [11 Je. 1785 - 7 Apr. 1842, Warren Co., OH] & Eliz. GIBBS, b. 24 Nov. 1782, NJ, m. 17 Mar. 1808, Warren Co., OH, & had Thomas G., b. 4 July 1810, Warren Co., OH, who had John E., of S. Lebanon, b. 1841, Union Twp. Edward & Eliz. also had Henry J., b. 15 Jan. 1818, who m. Martha FOX.

RootsWeb Family Trees has the New Jersey Dunham family, from which these descend. It also has other children of Edward, but Henry Jones is entered twice; "Harry" being a nickname for Henry.

Can you think of any other clues?

All I am certain of is that Francis Marion Dunham was my grandfathers parents. I am hoping to find out Francis parents

F. M. Dunham age 27 is listed with David Dunham in 1860 in Hamilton twp., Warren County, OH. In 1850, Francis M. Dunham is with David Dunham in Perry twp., Brown County, Ohio. David is my g-g-g grandfather through his son William Wilson Dunham. It seems Francis is David's son but he is not mentioned in David's will dated 26 Oct 1885, probated in Cincinnati. David married 4 times: 1st Lucina Chamberlain, 2nd Eleanor Heasley, 3rd Ann Yale Adams, 4th Mary. If David is Francis' father, then Eleanor is his mother.

I couldn't find Francis in OH in 1880. I did find Francis (age 36 born Ohio) and Catherine (age 30 born Ohio) with 4 children in Carondelet, St. Louis , MO in 1870. The first two were born in Ohio, one was born in Indiana (named David)and the youngest was born in Missouri. I always thought this was the same Francis from Warren Co., Ohio but now I'm not sure. Where in Ohio did you find them in 1880?

I must have typed a wrong date. sorry. Francis was my g grandfathere. They did come to St Louis and had five more children. how are you related to him.

He's the half brother of my g-g-grandfather William Wilson Dunham

this is my g grandfather. David is not listed as he was born in Indiana I think. He was born on the way to Missouri. How are you related to the Francis. There are a couple of Davids in the Dunham family My grandfather was Cornelius referred to as Neal

I have francis marion mother listed as ann. There were two francis marions in Ohio I found out a while back

maybe we should email each other and it would be easier to communicate all this inf faster do you know who francis mother was? mommoham@msn.com