Here's part of the original post (and the discrepancy chart):
Death Certificate, 1916 Peoria County, Illinois
Ca. 1840/1841 (estimated from age-birth date not stated on record)
1880 Census, Hancock County, Illinois
Ca. 1844/1845 (estimated from age)
1900 Census, Hancock County, Illinois
1910 Census, Peoria County, Illinois
Probably Hospital records
1883 Marriage to Martha PHELPS, Adams County, Illinois
Adams County, Illinois Poor House Records, August 1907
"about 63 years"
Insanity Case, Adams County, Illinois, September 1907
Insanity Case, Adams County, Illinois, September 1905
It turns out, based upon information contained in the widow's Civil War pension of Ira's sister Emmar (Sargent) Osenbaugh, that Ira was likely born near Darlington, Ontario, Canada in the early 1840s. Emmar would be a secondary source for her brother's place of birth, and actually, she never says anything about her brother specifically other than to say that he exists.
I need to add the information from Emmar to the chart and I really need to add a column for how much credence I give to each specific piece of information--not every statement listed in the chart can be viewed with the same level of confidence.
I've solved the question of Ira's parents. However, based upon what few records the family left I may not be able to pinpoint Ira's place or date of birth precisely.
In this situation, like many, it is about establishing relationships and connections. Precision with regards to time and place of birth may never be achieved.