I was looking through the 1870 census for our Robert McCormack near Winchester, Clark Co, Missouri and noticed on the previous page the second house away from Robert was a Suzan McCormack born in Indiana. Whoa!  I thought.  So I started piecing together everything I could on her and her family.  My theory is that she married one of Isham's brothers and that was why she lived so near to Isham's father Robert.  Below, I put all the info I have so far on this family trying to figure how she is related to us.  Her son William Robert McCormick went by both names.  Her mother Elizabeth Bruce was born in Ohio.  Some interesting facts: William married a Golliher, albeit a widow. Isham's daughter Rebecca married a Golliher.  Suzie lived near Isham's son James Isaac McCormac in Quincy.  One of William's son was named Carl, who also had a son named Carl, who may still be alive.  Also we are related to Bruces via the Goodwin line.
I am still searching but cannot find much else on these folks prior to 1870.  Missouri has lousy marriage records for Clark, Lewis and Marion counties, so I cannot find out who she married if she married them there.

(It is interesting how inconsistent folks were on their ages and where family members were born) 
1870 Clay Twp, Clark Co MO near Robert McCormack(hse # 63) 
Suzan McCormack 28 Indiana  household (#60) 
Nancy I.  10 Indiana 
Elizabeth A. 6 Indiana 
William R.  4 Indiana 
Mary J.  2 Missouri 
Elizabeth Bruce 56 Ohio 
Liddie Kindle  19 Indiana 
1880 United States Federal Census > Illinois > Adams > Quincy > District 23 
Anna McCormick 36  IN OH OH   {Suzan + Anna = Suzannah?)  head  listed as Widow 
Elizabeth McCormick 14  IN MO IN daughter 
William R. McCormick 12  IN MO IN  son 
Mary Jane McCormick 10  MO MO IN  daughter 
Luelle McCormick 8  MO MO IN  daughter 
Isabelle  Cooley 18  IN OH IN  daughter 
Elizabeth Bruce 78  OH PA PA  listed as mother 
City Directory:  William R. McCormick City: Quincy  State: IL  Occupation: laborer  Year: 1889, 1890  Location 2: r. 738 Olive  
Name: Robert McCormick City: Quincy   State: IL  Occupation: laborer  Year: 1889, 1890  Location 2: r. 738 Olive 
Name: Miss Luella McCormick City: Quincy  State: IL  Year: 1889, 1890  Location 2: r. 738 Olive   
Name: Mrs. Anna McCormick City: Quincy  State: IL  Year: 1889, 1890  Location 2: r. 738 Olive 
Name: Miss M. Jennie McCormick City: Quincy  State: IL  Year: 1889, 1890  Location 2: r. 738 Olive   
Name: Eugene Neighbors City: Quincy  State: IL  Occupation: teamster  Year: 1889, 1890  Location 2: r. rear 738 Olive  
Name: James I. McCormac City: Quincy  State: IL  Year: 1887, 1888  Business Name: McCormac & Doherty  Location 2: r. east side 12th, near Elm  "commission merchants" 
Marriage: 
NEIGHBORS, EUGENE and MCCORMICK, ELIZABETH 10/15/1882 / 00002363 ADAMS 
GALLIHER, HUGH   and CAVANAUGH, ELLA  06/15/1892    /     00007904 ADAMS 
MCCORMICK, WILLIAM R and GOLLIHER, ELLA 08/04/1897 / 00010902 ADAMS 
1900 Quincy, Adams Co, Illinois 
Susie A. McCormick   Feb.1849 IN OH OH  7 children, 5/6? still alive 
Henry Williams Oct.1851 Mo Mo Mo married 19 years  farmer 
Isabel Williams Sept 1861 IN IN IN  married 19 years  1 child born 1 still alive 
Effie J. Williams Nov 1887  IL MO IN 
Eugene Neighbors 1862  IL IL Germany 
Elizabeth A Neighbors 1862  IL MO IN 
Jessie M Neighbors 1885  
Josie M Neighbors 1888  
Edward L Neighbors 1891  
Bertha A Neighbors 1895  
Bertie A Neighbors 1895  
1910 Quincy, Adams Co, Illinois 
W.R. McCormick 1866 MO MO IN 
Ella M. McCormick 1868 Mo ?? IL 
Clarence McCormick 1900 IL MO MO 
Carl McCormick 1903 IL MO MO 
1920 Quincy, Adams Co, Illinois 
Robert W. McCormick 1867 IN  US US 
Ella M McCormick   1861 MO Ire IL 
Clarence E. McCormick 1901 IL IN MO 
Carl E. McCormick 1904 IL IN MO 
Sandefur Ernest (son in law) 1875 KY 
Sandefur Murtle M. 1896 (daughter)  IN IL MO  ? whose daughter? 
1930 Quincy, Adams, Illinois 
518 Kentucky St. Quincy 
Clarence E. McCormick 1900 IL  head  Machine operator Iron works 
Mildred C. McCormick 1903 IL  wife 
Robert W. McCormick 1867 IN  father  laborer plumbing company 
308 Kentucky St Quincy 
Carl E Mc Cormick 1904  head  shipping clerk  Hdev Store 
Laure M Mc Cormick 1913  wife 
Carl E Mc Cormick 1928  son 
Mary E Mc Cormick 1929  daughter 
deaths: 
MCCORMICK     WILLIAM      Y-84 0008886 1950-03-26 ADAMS    (born 1866) 
MC CORMICK, ELLA MARY  F/W  UNK  2010127 1925-03-09 ADAMS   QUINCY              25-03-11 
Carl McCormick Quincy, Adams, Illinois, Born: 22 Jun 1903 Died: Jan 1968 
Clarence McCormick 24 Jan 1900 Apr 1969 Quincy, Adams, Illinois 
Public Records: 
Name: Carl E McCormick Birth Date: Jan 1928 Street address: 33 N 12th  City: Quincy  County: Adams  
State: Illinois  Zip Code: 62301  Phone Number: 217-223-3112 

WWII enlistments 
Carl E McCormick 1903  Illinois  1 Aug 1942 U.S. At Large  Illinois