Clarence married Cecilia Mathida Schoenborn after 1930 in Illinois, USA. Cecilia (daughter of Aloysius Joseph Schoenborn and Emma Elizabeth Ehrstein) was born on 25 Mar 1907 in Olmsted, Pulaski County, Illinois, USA; died on 9 Nov 2002 in Daystar Care Center, Cairo, Alexander County, Illinois, USA; was buried in St. Catherine's Catholic Cemetery, Grand Chain, Pulaski County, Illinois, USA. [Group Sheet] [Family Chart]

1. Harold George Tennis was born on 2 Sep 1934 in Pulaski County, Illinois, USA; died on 8 Mar 1935 in Pulaski County, Illinois, USA; was buried on 9 Mar 1935 in St. Catherine's Catholic Cemetery, Grand Chain, Pulaski County, Illinois, USA.
2. Wilma Marie Tennis was born on 4 Jun 1936 in Pulaski County, Illinois, USA; died on 4 Jul 1998.
3. Leona Tennis
4. Carolyn Tennis was born on 25 Oct 1942 in Pulaski County, Illinois, USA; died on 17 Dec 2004 in Missouri, USA.