Linda: I've just done a follow-up posting with regard to my original inquiry about John Alexander and you can take a look at it for the additional information it contains but, in any event, based upon the information you provided me previously, I think we are probably researching two different John Alexanders -- not a big surprise when one is working with such a common surname and common first name.
I have now documents from Kentucky and Indiana that confirm that John Alexander was married twice, but neither wife was named Mary Thomas.John married his first cousin, Lucy Vest, in Boone County, Kentucky in 1834 and Nancy Allen in Martin County, Indiana, in 1892 at the age of 79.John's marriage license indicates that the 1892 marriage is his second.It also says he was born in Boone County, Kentucky.
We know, from both family and census lists, that John and Lucy Alexander eventually had 11 children, seven of whom are listed in the 1850 Martin County census, but the list does not include a son named Hiram, or any of the other children you have mentioned, Mary E., Issac, Nancy J., Eliza, and Franklin P. (although they did have a Mary M. and a Nancy Ann).
I also have found no evidence that would place this John Alexander in Hancock County, Indiana, at the time of Hiram's birth in 1838 or at any time before or after.We know that a John Alexander "of Boone County, Kentucky" bought farm land in Martin County, Indiana, in 1839.Hancock County is quite a ways to the north and east of Martin County, probably at least 100 miles.According to the censuses, John and Lucy were still living in Martin County in 1850, 1860 and 1870, so it would not appear to be the same John Alexander who moved his family to Mahaska County, Iowa, in 1855.Lucy Alexander died in 1888 in Martin County and John remarried in 1892, again in Martin County.And finally, John and his first wife, Lucy, are buried in the Pleasant Grove Cemetery in Martin County, Indiana, right next to John's older brother, James, James' wife, and, it would appear, James and John's parents, William and Rutha (the latter two headstones read "WA" and "RA").
All of this demonstrates the challenge of trying to trace common surnames, combined with common first names.I'm sure you are right:there probably was a John Alexander with a wife named Mary, who were both born in Hancock County, Indiana, who moved their family to Iowa in 1855.However, it seems clear to me that your ancestor, John Alexander, son of William, born in Hancock County, Indiana, between 1806 and 1811, is a different John Alexander than the John, son of William Alexander and Rutha Vest, who was born November 25, 1812 in Boone County, Kentucky.
I hope this helps you in your research.Best of luck.