Charles Edward Clark and Gladys Evelyn Darrah married June 30, 1921 and had one child, Joseph Edward Clark, born July 4, 1924.
Charles and Gladys were divorced March 25, 1949. 
Year: 1910; Census Place: Burlington Ward 5, Des Moines, Iowa; Roll: T624_401; Page: 9A; Enumeration District: 0013; FHL microfilm: 1374414
Ancestry.com. Iowa, State Census Collection, 1836-1925 [database on-line]. Provo, UT, USA: Ancestry.com Operations, Inc., 2007.
Original data: Microfilm of Iowa State Censuses, 1856, 1885, 1895, 1905, 1915, 1925 as well various special censuses from 1836-1897 obtained from the State Historical Society of Iowa via Heritage Quest.
Year: 1930; Census Place: Burlington, Des Moines, Iowa; Roll: 653; Page: 26A; Enumeration District: 0017; Image: 560.0; FHL microfilm: 2340388
Year: 1940; Census Place: Burlington, Des Moines, Iowa; Roll: T627_1156; Page: 11A; Enumeration District: 29-19
Ancestry.com. U.S., Social Security Death Index, 1935-2014 [database on-line]. Provo, UT, USA: Ancestry.com Operations Inc, 2011.
It may be possible to confirm family relationships with Charles by comparing test results with other carriers of his Y-chromosome or his mother's mitochondrial DNA.
However, there are no known yDNA or mtDNA test-takers in his direct paternal or maternal line.
It is likely that these autosomal DNA test-takers will share DNA with Charles: