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Mary Brennan — 1940 US Census Record
Model Tree available1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this Mary Brennan across the 1920, 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed), with identified parents Edward & Mary — first a head (b.~1908), then head of a 2-person household.
Age 32
b. ~1908
Female
Head
Born: Massachusetts
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | Brennan |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 32 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Occupation | Secretary |
| Industry | Contractor |
| Class of Worker | PW |
| Hours Worked | 38 |
| Income (1939) | 1000 |
| Highest Grade | H 4 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Secretary |
| Township / Ward | Boston City |
| Est. Birth Year | ~1908 |
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 |
|---|---|---|---|---|
| Patricia Brennan | Daughter | — | 3 | ~1937 |
| Mary Brennan | Head | — | 32 | ~1908 |
Census Appearances
1920
Suffolk, Massachusetts
Daughter, age 11
Suffolk, Massachusetts · implied b. ~1909 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Brennan |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Suffolk, Massachusetts
Daughter, age 22
Suffolk, Massachusetts · implied b. ~1908 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Brennan |
| Given Name | Mary A |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 22 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Occupation | Stenographer |
| Industry | Clothing Co. |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Head, age 32
Suffolk-County, Massachusetts · implied b. ~1908 — 2 household members
| Surname | Brennan |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 32 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Occupation | Secretary |
| Industry | Contractor |
| Class of Worker | PW |
| Hours Worked | 38 |
| Income (1939) | 1000 |
| Highest Grade | H 4 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
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 Brennan across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Edward Brennan (~0.92 confidence) and mother Mary Brennan (~0.92 confidence) and father John Brennan (~0.92 confidence) and mother Teresa Brennan (~0.92 confidence). The pedigree spans 1 generation with 4 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Edward Brennan
b. ~1879
Source father
● Household
· direct · ~0.92
Mother
Mary Brennan
b. ~1879
Source mother
● Household
· direct · ~0.92
Father
John Brennan
b. ~1884
Source father
● Household
· direct · ~0.92
Mother
Teresa Brennan
b. ~1885
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Brennan
Head · 1940 · age 32 · b. ~1908 · Massachusetts
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Suffolk-County, Massachusetts
Open full size
1940 US Federal Census — Suffolk-County, Massachusetts
Page Contents
27 people indexed on this census page (nara:1940:m-t0627-01668-00605)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Jean Drew | 5 | Daughter | — | Massachusetts |
| 42 | Beverly Drew | 4 | Daughter | — | Massachusetts |
| 43 | Fred Drew | 2 | Son | — | Massachusetts |
| 44 | James Drew | 0 | Son | — | Massachusetts |
| 46 | John Capelli | 24 | Head | New Worker | Massachusetts |
| 47 | Josephine Capelli | 23 | Wife | — | Pennsylvania |
| 48 | Louis Capelli | 1 | Son | — | Massachusetts |
| 49 | Angela La Rosa | 58 | Mother-in-law | Sample Maker | Italy |
| 51 | Kenneth Mc Laughlin | 45 | Head | Cab Driver | Massachusetts |
| 52 | Rocco Pocci | 62 | Head | Tailor | Italy |
| 54 | Catherine Tirone | 40 | Head | Bookkeeper | New Hampshire |
| 55 | Joseph Bowen | 47 | Lodger | Peddler | Massachusetts |
| 56 | Thomas Brogan | 64 | Lodger | Fireman | Eire |
| 57 | Harry Hartshorn | 54 | Head | Engineer | New Hampshire |
| 58 | Belle Hartshorn | 51 | Wife | Waitress | Massachusetts |
| 60 | John Spagnuolo | 24 | Head | Presser | Massachusetts |
| 61 | Mary Spagnuolo | 22 | Wife | Stitcher | Massachusetts |
| 62 | Louis Civeta | 57 | Head | Laborer | Italy |
| 63 | Carmella Civeta | 42 | Wife | — | Italy |
| 64 | Mary Civeta | 15 | Daughter | — | Massachusetts |
| 66 | Jacob Leiman | 73 | Head | Tailor | Latvia |
| 68 | Mary Brennan THIS PERSON | 32 | Head | Secretary | Massachusetts |
| 69 | Patricia Brennan | 3 | Daughter | — | Massachusetts |
| 71 | Martin Zirkin | 65 | Head | Foreman | Armenia |
| 72 | Jerry Zirkin | 36 | Son | — | Armenia |
| 73 | Catherine Hartigan | 56 | Head | Secretary | Massachusetts |
| 74 | Josephine E. Ritchie | 47 | Housekeeper | Housekeeper | Massachusetts |
Pedigree Summary
Mary
Gen 1 · 4 parents
~0.92
Max depth 4 (1900–1950 window)
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)