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Mary Mccarthy — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Mccarthy across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a daughter (b.~1922), then head of a 9-person household.
Age 18
b. ~1922
Female
Daughter
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | McCarthy |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 18 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1922 |
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.
9 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Dorothy Mccarthy | Daughter | — | 19 | ~1921 |
| Theresa Mccarthy | Daughter | — | 14 | ~1926 |
| Rita Mccarthy | Daughter | — | 20 | ~1920 |
| Mary Mccarthy | Daughter | — | 18 | ~1922 |
| Eileen Mccarthy | Daughter | — | 23 | ~1917 |
| James Mccarthy | Head | — | 51 | ~1889 |
| Maurice Mccarthy | Son | — | 16 | ~1924 |
| James Mccarthy | Son | — | 22 | ~1918 |
| Bridget Mccarthy | Spouse | — | 45 | ~1895 |
Census Appearances
1930
Cook, Illinois
Daughter, age 8
Cook, Illinois · implied b. ~1922 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McCarthy |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 8 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Daughter, age 18
Cook-County, Illinois · implied b. ~1922 — 9 household members
| Surname | McCarthy |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 18 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| 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 Mccarthy across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mccarthy
Daughter · 1940 · age 18 · b. ~1922 · Illinois
★ You are viewing this record
Sibling
James Mccarthy
Sibling · 1940 · age 22
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Eileen Mccarthy
Sibling · 1940 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Dorothy Mccarthy
Sibling · 1940 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Maurice Mccarthy
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Rita Mccarthy
Sibling · 1940 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Theresa Mccarthy
Sibling · 1940 · age 14
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-t0627-00957-00342)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Jack Prendergast | 34 | Head | Maintenance | Free State |
| 42 | Helen Prendergast | 32 | Wife | — | Illinois |
| 43 | Jack Prendergast | 6 | Son | — | — |
| 44 | Robert Prendergast | 1 | Son | — | — |
| 45 | John Mcguire | 32 | Head | Electrician | Illinois |
| 46 | Rose Mcguire | 32 | Wife | — | Illinois |
| 47 | Rosemary Mcguire | 3 | daughter | — | — |
| 48 | Joan Mcguire | 1 | daughter | — | — |
| 49 | Humphrey Sweeney | 55 | Head | Laborer | Free State |
| 50 | Nora Sweeney | 69 | Wife | — | Free State |
| 51 | Margaret Quinn | 43 | daughter | Beauty Operator | Illinois |
| 52 | Kate Carney | 75 | Lodger | — | Free State |
| 53 | John Mcguire | 56 | Head | Motorman | Free State |
| 54 | Rose Mcguire | 51 | Wife | — | Free State |
| 55 | James Mcguire | 28 | Son | New Worker | Illinois |
| 56 | Ralph Arnold | 32 | Head | Clerical | Illinois |
| 57 | Katherine Arnold | 34 | Wife | — | Illinois |
| 58 | Ralph F. Arnold | 4 | Son | — | — |
| 59 | Kathryn A. Arnold | 3 | daughter | — | — |
| 60 | Eileen M. Arnold | 0 | daughter | — | — |
| 61 | Walter (At) Moran | 39 | Head | Time Keeper | Free State |
| 62 | Catherine Moran | 37 | wife | — | Illinois |
| 63 | Margaret Moran | 14 | daughter | — | New York |
| 64 | John T. Moran | 12 | Son | — | Illinois |
| 65 | Walter E. Moran | 9 | Son | — | Illinois |
| 66 | Alfred Jr. Ulmer | 26 | Head | Plater | Illinois |
| 67 | Bernice Ulmer | 27 | Wife | — | Illinois |
| 68 | Albert Ulmer | 51 | Father | Watchman | Illinois |
| 69 | James Mccarthy | 51 | Head | Motorman | Free State |
| 70 | Bridget Mccarthy | 45 | Wife | — | Northern Ireland |
| 71 | Eileen Mccarthy | 23 | daughter | Secretary | Illinois |
| 72 | James Mccarthy | 22 | son | — | Illinois |
| 73 | Rita Mccarthy | 20 | daughter | Comptometer Operator | Illinois |
| 74 | Dorothy Mccarthy | 19 | daughter | — | Illinois |
| 75 | Mary Mccarthy THIS PERSON | 18 | daughter | — | Illinois |
| 76 | Maurice Mccarthy | 16 | son | — | Illinois |
| 77 | Theresa Mccarthy | 14 | daughter | — | Illinois |
| 78 | Michael Mcmahon | 45 | Head | Cab Driver | Illinois |
| 79 | Helen Mcmahon | 34 | wife | Waitress | Wisconsin |
| 80 | Robert Mcmahon | 8 | Son | — | Illinois |
Related Census Records
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)