Sebastian Family Genealogy Forum
I don't know of any Sebastians living in Oklahoma but Arthur Sebastian family lived in Siloam Springs, Arkansas about 1949-1951.
He and his wife had a farm just west of Spencer, IA about that time also. They had a son, Merrill and a daughter Patricia. The last I heard, Merrill still lived in Spencer.
Patricia I think married Harold Eninger and so far as I know live on a farm near Everly, Iowa. I visited briefly with Merrill a few years ago in Spencer.