Could this be them? 1880 census Union, Sedgwick, Kansas Chas. A. Soper, 32, born Il. Father born NJ, mother Ohio Catherine J. Soper, 30, born Canada parents born Ireland Ella Soper, 7, born Kansas William, 5, born Kansas Richard A., 39 (brother of Charles)
From familysearch.org Charles Arthur Soper married Catherine Carol and had children Ella abt. 1873, Jemie abt. 1887 and Stella abt. 1890.