Beware, there is a George Twyman born England 1848 that married a Harriet ? and both land in the 1880 census in St Clair IL. They are buried in Morgan County Missouri I believe. This is not George Buford Twyman of Missouri who was in the confederate home in Higginsville. He was born in Kentucky in 1820. His wife was Eliza Griffith and they were married in 1840 in Cass County, MO. She died APR 02, 1873 in Cass county, He entered the Confederate home with his son shortly thereafter. His son, Daniel, born 1840 died in the Higginsville home in 1919. Fold3 has GB's application on file for the home. He spent a good portion of the war in Texas. He was a wagonmaster/teamster. The Higginsville records do not have a date for George's date. I've noted some confusion on some web sites where the two George's are conflated.
His son George Nelson Twyman death certificate is here: https://www.sos.mo.gov/images/archives/deathcerts/1949/1949_00011805.PDF