Calvin is the son of James A. and Sarah M. Thomason Davis. His wife was Clara. He was a farmer.

Info from: Illinois, Deaths & Stillbirths, 1916-1947.

Obituary:
C.M. Davis Passed Away
Funeral Held Monday Afternoon at the Christian Church
Calvin Monroe Davis died Saturday at 5:15 pm at his home four miles south of Bethany.
He had been seriously ill for eight weeks with uremic poisoning and complications of disease due to old age. All that loving hearts and hands could do to relieve his suffering was done, but to no avail. God relieved his suffering and he passed peacefully on.
Mr. Davis was born in Boone County, Indiana on December 1, 1852 and died July 21, 1934 at the age of 81 years, 7 months and 20 days. He was the son of James and Sarah Davis who with two brothers, Ammon and John, and sister Lucy preceded him in death. Mr. Davis came to Moultrie County, Illinois with his parents at the age of 17 years. He has spent the rest of his entire life in Moultrie County. He lived for 44 years on the farm on which he died.
He was married to Anna Moreland Clark in the year of 1878. She died ten years after their marriage. To this union was born five children all of whom are still living.
He was married to Clara Garver of Decatur November 23, 1893 and to this union was born nine children, two baby girls preceding him in death.
He joined the Wilburn Creek Church soon after his second marriage. He was a loving husband, devoted father and a good neighbor. He leaves to mourn his death his devoted wife and 12 children, namely: Irvin and Walter of Garden Grove, Iowa, Carrie Arnold of Tampa, Florida, Della Clark of Springfield, Rosa Marshall, Flossie Sanner, Ollis, Virgil and Zera of Bethany, Calvin Jr. of Sullivan, Freda Vandeveer of Filson and Cleo Homer of Chicago, a step daughter, Josie Clark Hilliard of Clio, Iowa, 31 grandchildren and 5 great grandchildren, one sister, Josephine McReynolds of Kansas and many relatives and friends.
Interment was in the Bethany Cemetery.