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Mary Leahy — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Leahy across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a spouse (b.~1886), then head of a 4-person household.
Age 54
b. ~1886
Female
Spouse
Born: Ireland
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Leahy |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 54 |
| Marital Status | Married |
| Birthplace | Ireland |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Additional Details | |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
| Township / Ward | Chicago |
| Est. Birth Year | ~1886 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| James Leahy | Son | — | 24 | ~1916 |
| Mary Leahy | Spouse | — | 54 | ~1886 |
| Maurice Leahy | Head | — | 54 | ~1886 |
| Anna Leahy | Daughter | — | 22 | ~1918 |
Census Appearances
1930
Cook, Illinois
Other, age 44
Cook, Illinois · implied b. ~1886 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leahy |
| Given Name | Mary |
| Relationship to Head | Wife-H |
| Sex | F |
| Color / Race | White |
| Age | 44 |
| Marital Status | Married |
| Birthplace | Ireland |
| Naturalization Status | Naturalized |
| Year of Immigration | 1900 |
| Age at First Marriage | 25 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read/Write | Yes |
| Mother Tongue | English |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
1940
Cook-County, Illinois
Spouse, age 54
Cook-County, Illinois · implied b. ~1886 — 4 household members
| Surname | Leahy |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 54 |
| Marital Status | Married |
| Birthplace | Ireland |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
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 Leahy across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Leahy
Spouse · 1940 · age 54 · b. ~1886 · 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 — 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-t0627-00949-00163)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Mary Higgins | 26 | Daughter | Typist | Wisconsin |
| 2 | Patrick Higgins | 21 | Son | File Clerk | Illinois |
| 3 | Maurice E. Leahy | 54 | Head | Order Clerk | Irish Free State |
| 4 | Mary Leahy THIS PERSON | 54 | Wife | — | Ireland |
| 5 | James Leahy | 24 | Son | General Office | Illinois |
| 6 | Anna M. Leahy | 22 | Daughter | School Teacher | Illinois |
| 7 | Lucille Logan | 45 | Head | — | Illinois |
| 8 | Cornelius P. Baldwin | 40 | Head | Fireman | Illinois |
| 9 | Elizabeth Baldwin | 32 | Wife | Matron | Illinois |
| 10 | Elizabeth M. Baldwin | 12 | Daughter | — | Illinois |
| 11 | Cornelius J. Baldwin | 11 | Son | — | Illinois |
| 12 | Edward Baldwin | 6 | Son | — | Illinois |
| 13 | Joseph M. Maurer | 47 | Head | Painter | Illinois |
| 14 | Clara Maurer | 44 | Wife | — | Illinois |
| 15 | Ethel Maurer | 23 | Daughter | Binder (Factory) | Illinois |
| 16 | Dorothy Maurer | 19 | Daughter | File Clerk | Illinois |
| 17 | Joseph Maurer | 16 | Son | — | Illinois |
| 18 | Charles Maurer | 13 | Son | — | Illinois |
| 19 | Frances Maurer | 12 | Daughter | — | Illinois |
| 20 | Michaela Curran | 63 | Head | Chauffeur | Ohio |
| 21 | Edward J. Curran | 23 | Son | Special Delivery Messenger | Illinois |
| 22 | Rocco Panneralla | 48 | Head | Shoe Rebuilder | Italy |
| 23 | Louise Panneralla | 43 | Wife | — | Illinois |
| 24 | Eugene Panneralla | 23 | Son | Laborer | Illinois |
| 25 | Theresa Panneralla | 21 | Daughter | House Worker | Illinois |
| 26 | Loretta Panneralla | 20 | Daughter | Laborer | Illinois |
| 27 | Francis Panneralla | 18 | Son | Laborer | Illinois |
| 28 | Vincent Panneralla | 16 | Son | — | Illinois |
| 29 | Rosemary Panneralla | 12 | Daughter | — | Illinois |
| 30 | Joseph Panneralla | 4 | Son | — | Illinois |
| 31 | Ronald Panneralla | 1 | Son | — | Illinois |
| 32 | John J. Massey | 71 | Head | Laborer | Wisconsin |
| 33 | Emma Massey | 70 | Wife | — | Ohio |
| 34 | Charles J. Goss | 42 | Head | Police Officer | Illinois |
| 35 | Kathleen M. Goss | 39 | Wife | Matron | Illinois |
| 36 | Bernadette Goss | 17 | Daughter | — | Illinois |
| 37 | John P. Corridon | 42 | Head | Stationary Fireman | Irish Free State |
| 38 | Mary Corridon | 37 | Wife | — | Ireland |
| 39 | Lawrence Corridon | 9 | Son | — | Illinois |
| 40 | Anna M. Corridon | 7 | 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)