This is my sister's husband's Great-Grandfather.  William Riley McCormic has been so hard to search down.  
We have only found him in the 1900 & 1910 Census.  H is buried at Sheridan Cemetery, Auburn NE.  
Alice has the tombstone pictures for both.
 
Source: Alice Lechner Huey
William McCormic was born 17 July 1848, VA, died July 23, 1917 in Auburn, Nemaha Co., Nebr.  
Married Matilda (Martha) Jane Maxey, b. June 16,  1860 in VA. (tombstone reads May 3, 1860), 
died Sept. 14, 1898 in Nemaha Co., Nebr., buried in Linden Cemetery, Nemaha Co., Nebr.
They were married Jan. 8, 1876 in Roanoke, Lynchburg Co., VA.  
 
Matilda's parents were: Levi & Martha Ann (Goode) Maxey
Williams parents are unknown.
 
Children: 
Charles Levi McCormic
Nancy Victoria Martha Jane McCormic
Obera Ann McCormic
Minerva Louise McCormic
Sally Bett McCormic
William Jackson McCormic
Aaron Harrison McCormic
James Eugene McCormic
Peter McCormic
Current Harper McCormic
 
Source: Ancestry.com
1900 Census
Glen Rock Precinct
Dist. 92, Sheet 7A Dwelliing 127
Image 12 of 19
Mc connie, Wm, age 51, born July 1848 Va Va Va Owned House, could read & write, farmer.
         , Sally, dau., age 17, born Dec. 1882 Va Va Va could read & write.
         , Willie, son, age 14, born July 1885 Va Va VA could read & write.
         , Current, dau. age 6, born June 1893 Va VA Neb.