According to his marriage record from ancestry, , unless I am mistaken, his parents are listed as
Fred Klein & Nettie Christie.
He is listed as being married to Alice M Mero on May 26, 1926 in Detroit Michigan.
Here is what I believe to be him in the 1910 US census.
"United States Census, 1910," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MLTL-N2W : accessed 18 June 2018), Clarence H Klein in household of Fred Klein, Detroit Ward 9, Wayne, Michigan, United States; citing enumeration district (ED) ED 130, sheet 10A, family 226, NARA microfilm publication T624 (Washington D.C.: National Archives and Records Administration, 1982), roll 683; FHL microfilm 1,374,696.
Here is a bit more, a marriage record of what appears to be his older sister Lillian, Gives pretty much the same information about the parents as his marriage record did.
"Ontario Marriages, 1869-1927," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:KSZX-3KF : 11 March 2018), Fred Klein in entry for Frederick Gordon Mcgregor and Lillian Josephine Klein, 03 Mar 1908; citing registration , Windsor, Essex, Ontario, Canada, Archives of Ontario, Toronto; FHL microfilm 1,871,866.
Lastly, to tie it all in, is the 1900 census record for Fred Klein and family. While Clarence has yet to be born, we do se Lillian listed.
"United States Census, 1900," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M913-YT8 : accessed 18 June 2018), Frederick Klein, Detroit city Ward 11, Wayne, Michigan, United States; citing enumeration district (ED) 124, sheet 3B, family 62, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, 1972.); FHL microfilm 1,240,751.
I'm not sure why the slight discrepancy in names of the mother, Nettie as apposed to Mary. My best guess is that Nettie is a nickname perhaps and Mary is the proper name.
I hope this helps.
craig