There was a true O'Dea hero living in Southern Illinois in the late 1800's.
John O'Dea Private of Co D 8th Regiment Missouri Volunteer Infantry won the Medal of Honor for actions at the Seige of Vicksburg in May 1863.He left the Army due to wounds received at Vicksburg and elsewhere.An extensive pension record exists of John at the National Archives.
John was born in Limerick in 1839 and joined the 8th Missouri on June 14, 1861.He saved some comrades who were pinned down by rebel fire in the assault on Ft. Pemberton at Vicksburg in May 1863.A nearby shell explding cost him his hearing in 1 ear.He also suffered a groin injury from which he never fully recovered.
After the war he resided in Blommington, IL.He married and had 3 children.He was a blacksmith in Bloomington.He died at the Old Soldiers Home in Quincy, IL on july 2, 1905.
This is from notes I took from original documents in his pension record at the Natl Archives some years ago