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Mary Leahy — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Sussex-County, New Jersey
Our Model Tree links this Mary Leahy across the 1930 and 1940 US Censuses in Sussex-County, New Jersey (XGBoost, ~Confirmed) — first a head (b.~1872), then head of a 2-person household.
Age 68
b. ~1872
Female
Head
Born: New Jersey
Widowed
1940 Census Record Details
| Census Year | 1940 |
| Location | Sussex-County, New Jersey |
| Surname | Leahy |
| Given Name | Mary C. |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 68 |
| Marital Status | Widowed |
| Birthplace | New Jersey |
| 1935 Residence (City) | Hopatcong Borough |
| 1935 Residence (County) | Sussex |
| Additional Details | |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Township / Ward | Hopatcong Borough |
| Est. Birth Year | ~1872 |
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.
2 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Leahy | Head | — | 68 | ~1872 |
| John Leahy | Son | — | 37 | ~1903 |
Census Appearances
1930
Sussex, New …
Spouse, age 58
Sussex, New Jersey · implied b. ~1872 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leahy |
| Given Name | Mary C. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 58 |
| Marital Status | Married |
| Birthplace | New Jersey |
| Age at First Marriage | 29 |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Irish Free State |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1940
Sussex-County, New …
Head, age 68
Sussex-County, New Jersey · implied b. ~1872 — 2 household members
| Surname | Leahy |
| Given Name | Mary C. |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 68 |
| Marital Status | Widowed |
| Birthplace | New Jersey |
| 1935 Residence (City) | Hopatcong Borough |
| 1935 Residence (County) | Sussex |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
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.
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This person
Anchor record
Mary Leahy
Head · 1940 · age 68 · b. ~1872 · New Jersey
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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 — Sussex-County, New Jersey
Open full size
1940 US Federal Census — Sussex-County, New Jersey
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-02384-00337)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Henry Ullrich | 50 | Head | Laborer | New Jersey |
| 42 | Albert Ullrich | 18 | Son | Laborer | New Jersey |
| 43 | Edward Ullrich | 15 | Son | — | New Jersey |
| 44 | Harry Von Klein | 65 | Head | Laborer | England |
| 45 | John Huber | 67 | Head | Janitor | Germany |
| 46 | Gunnine Huber | 62 | Wife | — | New Jersey |
| 47 | Walter English | 35 | Head | Carpenter | New Jersey |
| 48 | Helen English | 31 | Wife | Secretary | New Jersey |
| 49 | Ignazio Carubba | 45 | Head | Tailor | Italy |
| 50 | Frances Carubba | 41 | Wife | — | New York |
| 51 | Nancy Carubba | 14 | Daughter | — | New York |
| 52 | Mary Carubba | 9 | Daughter | — | New Jersey |
| 53 | Angelo J. Carubba | 7 | Son | — | New Jersey |
| 54 | Margery J. Carubba | 1 | Daughter | — | New Jersey |
| 55 | Ralph Bar | 31 | Head | Laborer | Pennsylvania |
| 56 | Alwynella Bar | 20 | Wife | — | New Jersey |
| 57 | Alice Bar | 3 | Daughter | — | New Jersey |
| 58 | Mary C. Leahy THIS PERSON | 68 | Head | — | New Jersey |
| 59 | John Leahy | 37 | Son | Truck Driver | New Jersey |
| 60 | John Post | 53 | Head | Proprietor | Canada |
| 61 | Clara Post | 50 | Wife | — | New Jersey |
| 62 | Otto Dingaam | 34 | Head | Engineer | Germany |
| 63 | Anna Dingaam | 35 | Wife | — | Germany |
| 64 | John Otto Dingaam | 1 | Son | — | New Jersey |
| 65 | Gustave Huber | 65 | Head | Caretaker | Switzerland |
| 66 | Elizabeth Huber | 57 | Wife | — | New York |
| 67 | Albert H. Huber | 30 | Son | Engineer (Sta) | New York |
| 68 | Alice M. Huber | 21 | Daughter | Physician | New Jersey |
| 69 | Amy Bertha Alsing | 25 | Daughter | — | New York |
| 70 | Beatrice Alsing | 13 | Daughter | — | New York |
| 71 | Joyce Alsing | 10 | Daughter | — | New York |
| 72 | Guy Graham | 52 | Head | — | New York |
| 73 | Hugo Noble | 36 | Head | Carpenter | New Jersey |
| 74 | Marjorie Noble | 35 | Wife | — | Pennsylvania |
| 75 | Raymond Decker | 54 | Head | Proprietor | New Jersey |
| 76 | Katherine Decker | 52 | Wife | — | Germany |
| 77 | Virginia Decker | 22 | Daughter | Cashier | New Jersey |
| 78 | Raymond Decker | 18 | Son | Delivery | New Jersey |
| 79 | Marion Decker | 12 | Daughter | — | New Jersey |
| 80 | Martin Lord | 45 | Head | Golf Pro | New York |
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)