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Mary Mackey — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Mackey across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a daughter (b.~1911), then head of a 5-person household.
Age 29
b. ~1911
Female
Daughter
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Mackey |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Income (1939) | 0 |
| Highest Grade | C-3 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago |
| Est. Birth Year | ~1911 |
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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Mackey | Daughter | — | 29 | ~1911 |
| James Mackey | Son | — | 12 | ~1928 |
| Thomas Mackey | Head | — | 59 | ~1881 |
| William Mackey | Son | — | 22 | ~1918 |
| Bernard Mackey | Son | — | 17 | ~1923 |
Census Appearances
1930
Cook, Illinois
Other, age 18
Cook, Illinois · implied b. ~1912 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mackey |
| Given Name | Mary |
| Relationship to Head | Servant |
| Sex | F |
| Color / Race | White |
| Age | 18 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Czechoslovakia |
| Mother's Birthplace | Czechoslovakia |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Daughter, age 29
Cook-County, Illinois · implied b. ~1911 — 5 household members
| Surname | Mackey |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Income (1939) | 0 |
| Highest Grade | C-3 |
| 1935 Residence | Same house |
| 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 Mackey across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mackey
Daughter · 1940 · age 29 · b. ~1911 · Illinois
★ You are viewing this record
Sibling
William Mackey
Sibling · 1940 · age 22
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Bernard Mackey
Sibling · 1940 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
James Mackey
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Cook-County, Illinois
Open full size
1940 US Federal Census — Cook-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01020-00870)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | William G. Henrichs | 56 | Head | Office Manager | Illinois |
| 42 | Nora A. Henrichs | 55 | Wife | — | Indiana |
| 43 | Carl Buchmann | 56 | Head | House Painter | Sweden |
| 44 | Hilda Buchmann | 51 | Wife | — | Sweden |
| 45 | Elsie Buchmann | 23 | Daughter | Typist | Illinois |
| 46 | Honora Moore | 64 | Head | — | New York State |
| 47 | Helen L. Moore | 30 | Daughter | Teacher | Illinois |
| 48 | Thomas C. Mackey | 59 | Head | Engineer | Illinois |
| 49 | Mary Mackey THIS PERSON | 29 | Daughter | — | Illinois |
| 50 | Bernard Mackey | 17 | Son | — | Illinois |
| 51 | James Mackey | 12 | Son | — | Illinois |
| 52 | William Mackey | 22 | Son | Construction Worker | Illinois |
| 53 | Morris Wellman | 48 | Head | Wholesale Salesman | Russia |
| 54 | Minora Wellman | 39 | Wife | — | Illinois |
| 55 | Geraldine Wellman | 15 | Daughter | — | Illinois |
| 56 | Meriam Wellman | 11 | Daughter | — | Illinois |
| 57 | Herbert Meyer | 42 | Head | Meat Dealer | Illinois |
| 58 | Sarah Meyer | 38 | Wife | — | Illinois |
| 59 | Ramona Meyer | 15 | Daughter | — | Illinois |
| 60 | Marilyn Meyer | 10 | Daughter | — | Illinois |
| 61 | Samuel Eneff | 52 | Head | Proprietor Pharmacist | Russia |
| 62 | Bessie Eneff | 48 | Wife | Asst Pharmacist | Russia |
| 63 | Herbert Eneff | 16 | Son | — | Illinois |
| 64 | Jacob Cohen | 38 | Head | Accountant | Illinois |
| 65 | Esther Cohen | 35 | Wife | — | Illinois |
| 66 | Donna Rae Cohen | 11 | Daughter | — | Illinois |
| 67 | Sigmund Cohen | 7 | Son | — | Illinois |
| 68 | Nema Johnson | 65 | Servant | Servant | Sweden |
| 69 | Mark Gustaf | 38 | Head | Proprietor Salesman | Illinois |
| 70 | Rae Gustaf | 35 | Wife | — | Poland |
| 71 | Robert Gustaf | 9 | Son | — | Illinois |
| 72 | Maria Samuels | 46 | Maid | Servant | Tennessee |
| 73 | John Cleary | 38 | Head | Lawyer | England |
| 74 | Nellie Cleary | 34 | Wife | — | Illinois |
| 75 | Robert Cleary | 10 | Son | — | Illinois |
| 76 | James Cleary | 4 | Son | — | Illinois |
| 77 | Catherine Colby | 31 | Maid | Servant | Wisconsin |
| 78 | Martin Chmela | 42 | Head | Janitor | Austria |
| 79 | Agnes Chmela | 44 | Wife | — | Austria |
| 80 | Eleanor Chmela | 17 | Daughter | — | 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)