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Mary Mckay — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Iroquois-County, Illinois
Our Model Tree links this Mary Mckay across the 1930 and 1940 US Censuses in Iroquois-County, Illinois (XGBoost, ~Confirmed) — first a spouse (b.~1896), then head of a 6-person household.
Age 44
b. ~1896
Female
Spouse
Born: Illinois
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Iroquois-County, Illinois |
| Surname | McKay |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 44 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Clifton |
| 1935 Residence (County) | Iroquois |
| Additional Details | |
| Highest Grade | No 8 |
| 1935 Residence | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chebanse Township |
| Est. Birth Year | ~1896 |
Household Members
Census records only state relationship to the household head.
Pairwise kinship is derived (~90–95% accurate), not recorded.
Step/blended families and boarders can break it.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| William Mckay | Head | — | 47 | ~1893 |
| Mary Mckay | Spouse | — | 44 | ~1896 |
| Margaret Mckay | Daughter | — | 8 | ~1932 |
| Harold Mckay | Son | — | 18 | ~1922 |
| Gerald Mckay | Son | — | 2 | ~1938 |
| Donald Mckay | Son | — | 21 | ~1919 |
Census Appearances
1930
Iroquois, Illinois
Other, age 34
Iroquois, Illinois · implied b. ~1896 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McKay |
| Given Name | Mary O |
| Relationship to Head | Wife-H |
| Sex | F |
| Color / Race | White |
| Age | 34 |
| Marital Status | Married |
| Birthplace | Illinois |
| Age at First Marriage | 22 |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Iroquois-County, Illinois
Spouse, age 44
Iroquois-County, Illinois · implied b. ~1896 — 6 household members
| Surname | McKay |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 44 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Clifton |
| 1935 Residence (County) | Iroquois |
| Highest Grade | No 8 |
| 1935 Residence | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
Model Tree
An inferred pedigree reconstructed from census links — up to 4 generations within the 1900–1950 window. Closer generations are built from household co-residence; deeper ones are bridged by following a relative to their own childhood census. Confidence compounds and weakens with each generation.
Our Model Tree links Mary Mckay across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mckay
Spouse · 1940 · age 44 · b. ~1896 · Illinois
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Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Iroquois-County, Illinois
Open full size
1940 US Federal Census — Iroquois-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00813-00378)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Herman Jensen | 45 | Head | Farmer | Illinois |
| 42 | Orra Jensen | 38 | Wife | — | Illinois |
| 43 | Eileen Jensen | 15 | Daughter | — | Illinois |
| 44 | Betty Ann Jensen | 4 | Daughter | — | Illinois |
| 45 | William F. Mckay | 47 | Head | Farmer | Illinois |
| 46 | Mary Mckay THIS PERSON | 44 | Wife | — | Illinois |
| 47 | Donald Mckay | 21 | Son | Farm Laborer | Illinois |
| 48 | Harold A. Mckay | 18 | Son | — | Illinois |
| 49 | Margaret Mary Mckay | 8 | Daughter | — | Illinois |
| 50 | Gerald Mckay | 2 | Son | — | Illinois |
| 51 | Roy Jensen | 42 | Head | Farmer | Illinois |
| 52 | Alice Jensen | 41 | Wife | — | Illinois |
| 53 | Harold Jensen | 19 | Son | Farm Laborer | Illinois |
| 54 | Arnold Jensen | 16 | Son | — | Illinois |
| 55 | Norma Lee Jensen | 11 | Daughter | — | Illinois |
| 56 | Maynard Jensen | 2 | Son | — | Illinois |
| 57 | Duane Miller | 27 | Head | Farmer | Illinois |
| 58 | Leona Q. Miller | 27 | Wife | — | Illinois |
| 59 | Dallas Miller | 5 | Son | — | Illinois |
| 60 | Betty Jane Miller | 2 | Daughter | — | Illinois |
| 61 | Clara Knipprath | 70 | Head | — | Illinois |
| 62 | Marie Morel | 59 | Head | — | Illinois |
| 63 | Julian Doyen | 75 | Lodger | — | Belgium |
| 64 | Emile Mercier | 53 | Head | Farmer | Belgium |
| 65 | Earnest Mercier | 84 | Father | — | Belgium |
| 66 | Mary Mercier | 74 | Mother | — | Belgium |
| 67 | Edward Mercier | 58 | Brother | Farm Laborer | Belgium |
| 68 | Eva Mercier | 23 | Niece | — | Illinois |
| 69 | Fred Prue | 69 | Head | Farmer | Illinois |
| 70 | Dora D. Prue | 64 | Wife | — | Illinois |
| 71 | Annie Prue | 44 | Daughter | — | Illinois |
| 72 | Roy Prue | 41 | Son | Farm Laborer | Illinois |
| 73 | Vivian Prue | 35 | Daughter | — | Illinois |
| 74 | Russell D. Lambert | 26 | Head | Farmer | Illinois |
| 75 | Helen Lambert | 24 | Wife | — | Illinois |
| 76 | Betty Jean Lambert | 4 | Daughter | — | Illinois |
| 77 | Lois Marie Lambert | 3 | Daughter | — | Illinois |
| 78 | Marcella Lambert | 2 | Daughter | — | Illinois |
| 79 | Sandra Lee Lambert | 0 | Daughter | — | Illinois |
| 80 | Florent Bertrand | 35 | Head | Farmer | Illinois |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1940 United States Federal Census (NARA). Our Model Tree links this person across census decades using XGBoost-based record linkage, with per-link confidence scores. Household corroboration strengthens the signal when co-residents appear on the same census pages in multiple years.
Source: National Archives and Records Administration (NARA)