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Mary Maguire — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Middlesex-County, Massachusetts
Our Model Tree links this Mary Maguire across the 1930 and 1940 US Censuses in Middlesex-County, Massachusetts (XGBoost, ~Confirmed) — first a daughter (b.~1919), then head of a 9-person household.
Age 21
b. ~1919
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Middlesex-County, Massachusetts |
| Surname | Maguire |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Lowell City |
| 1935 Residence (County) | Middlesex |
| Additional Details | |
| Occupation | Assembler |
| Industry | Electric Switch |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Assembler |
| Township / Ward | Lowell City |
| Est. Birth Year | ~1919 |
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 |
|---|---|---|---|---|
| Mary Maguire | Daughter | — | 21 | ~1919 |
| Bernadette Maguire | Daughter | — | 15 | ~1925 |
| Agnes Maguire | Daughter | — | 17 | ~1923 |
| Dorothy Maguire | Daughter | — | 10 | ~1930 |
| Philip Maguire | Son | — | 6 | ~1934 |
| James Maguire | Son | — | 19 | ~1921 |
| Alice Maguire | Daughter | — | 23 | ~1917 |
| Minnie Maguire | Spouse | — | 42 | ~1898 |
| Peter Maguire | Head | — | 44 | ~1896 |
Census Appearances
1930
Middlesex, Massachusetts
Daughter, age 10
Middlesex, Massachusetts · implied b. ~1920 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Maguire |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Occupation | Teacher |
| Industry | Piano |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Middlesex-County, Massachusetts
Daughter, age 21
Middlesex-County, Massachusetts · implied b. ~1919 — 9 household members
| Surname | Maguire |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Lowell City |
| 1935 Residence (County) | Middlesex |
| Occupation | Assembler |
| Industry | Electric Switch |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| 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 Maguire across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
Mary Maguire
Daughter · 1940 · age 21 · b. ~1919 · Massachusetts
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Sibling
Alice Maguire
Sibling · 1940 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
James Maguire
Sibling · 1940 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Dorothy Maguire
Sibling · 1940 · age 10
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Bernadette Maguire
Sibling · 1940 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Philip Maguire
Sibling · 1940 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Agnes Maguire
Sibling · 1940 · age 17
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 — Middlesex-County, Massachusetts
Open full size
1940 US Federal Census — Middlesex-County, Massachusetts
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01694-00515)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Maguire, Michael J Welch | 32 | Br-in-law | Fireman | Massachusetts |
| 2 | Peter Maguire | 44 | Head | Commissioner | Massachusetts |
| 3 | Minnie Maguire | 42 | Wife | — | Massachusetts |
| 4 | Alice Maguire | 23 | Daughter | Clerk | Massachusetts |
| 5 | Mary Maguire THIS PERSON | 21 | Daughter | Assembler | Massachusetts |
| 6 | James Maguire | 19 | Son | Battery Boy | Massachusetts |
| 7 | Agnes Maguire | 17 | Daughter | — | Massachusetts |
| 8 | Bernadette Maguire | 15 | Daughter | — | Massachusetts |
| 9 | Dorothy Maguire | 10 | Daughter | — | Massachusetts |
| 10 | Philip Maguire | 6 | Son | — | Massachusetts |
| 11 | Thomas D Tetford | 57 | Head | Card Room | New York |
| 12 | Grace Tetford | 23 | Daughter | Clerk | Massachusetts |
| 13 | Kathleen Tetford | 20 | Daughter | — | Massachusetts |
| 14 | Samuel J Burt | 73 | Head | Chauffeur | England |
| 15 | Lillian Burt | 73 | Wife | — | England |
| 16 | Alfred Luiz | 27 | Head | Laborer | Massachusetts |
| 17 | Rose Luiz | 31 | Wife | Knitter | Massachusetts |
| 18 | James Luiz | 3 | Son | — | Massachusetts |
| 19 | Gene Costa | 40 | Head | Weaver | Portugal |
| 20 | Marcella Costa | 40 | Wife | — | Portugal |
| 21 | Lena Costa | 16 | Daughter | — | Massachusetts |
| 22 | Mary Costa | 13 | Daughter | — | Massachusetts |
| 23 | Hilda Costa | 10 | Daughter | — | Massachusetts |
| 24 | Albert Costa | 5 | Son | — | Massachusetts |
| 25 | Hazel Calhoun | 34 | Head | — | Massachusetts |
| 26 | Jacqueline Calhoun | 9 | Daughter | — | Massachusetts |
| 27 | William Calhoun | 7 | Son | — | New York |
| 28 | James Calhoun | 5 | Son | — | Massachusetts |
| 29 | Leo Calhoun | 2 | Son | — | Massachusetts |
| 30 | Patrick Boland | 65 | Head | — | Irish Free State |
| 31 | Mary Boland | 62 | Wife | — | Irish Free State |
| 32 | Gerald Boland | 31 | Son | Dyer | Massachusetts |
| 33 | Mary Boland | 26 | Daughter | Tally Clerk | Massachusetts |
| 34 | William Mccormick | 40 | Head | Laborer | Massachusetts |
| 35 | Lillian Mccormick | 33 | Wife | Doffer | Massachusetts |
| 36 | Billy Mccormick | 6 | Son | — | Massachusetts |
| 37 | Nancy Mccormick | 5 | Daughter | — | Massachusetts |
| 38 | Maurice Mccormick | 4 | Daughter | — | Massachusetts |
| 39 | Mary Mchugh | 57 | Head | Burler | Massachusetts |
| 40 | Martin Mchugh | 49 | Brother | Laborer | Massachusetts |
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)