Looking for info. On Theophilus Downs. This is what we believe is true, but can not find any additional information past that below:
Theophilus Downs b. c. 1804, MD; d. 16 Feb 1871, Fulton Co., IL. Theo. possibly married 29 Apr 1834, Carroll Co., OH to Catherine Mansfield b. c.1819, MO d. 28 Oct 1889, Fulton Co., IL. Both are buried in Blackaby Cemetery near Cuba, IL. Back when I first took an interest in genealogy in 1984, I met with a relative of my grandfathers named Moneta Downs. She was an older, single lady with no children. She died within 2 weeks of our first meeting. I have no idea what became of her research. I always thought her father and my great-great grandfather, were brothers, but now I am seeing reports of Charles F. Downs b. 14 Nov 1874 / d. 15 Jan 1956 (S/O George W. Downs & G/S of Theophilus) was an only child.
Have you checked out the 1850 cens for Theophilus & Catherine Downs in Knox County, Ohio. (They also have a son George born in Ohio plus older children including a son William). Might be worth checking this rabbit trail.