In the census records for 1850 Summit, Crawford, PA, it appears that their children were b. in OH in about 1835, 1837 and 1839. Their son James from the 1850 and 1860 census appears to be about 85 and living with his son DeForest Truax in Summit, Crawford, PA in the 1920 census. If James Truax b. abt. 1835 OH d. in Summit, a newspaper obit. or death record might indicate where he was b. in OH. The 1840 census for Franklin, Knox Co., OH has several Truax listed: John Truax, Nathaniel Truax, and a G.F. or J.F. Truax. If James was b. Knox Co., OH, you might want to examine the latter Truax to see if he might have actually been your Peter F. Truax living near his relatives.