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Mary Monahan — 1940 US Census Record
Model Tree available1940 United States Federal Census · Essex-County, Massachusetts
Our Model Tree links this Mary Monahan across the 1920, 1930 and 1940 US Censuses in Essex-County, Massachusetts (XGBoost, ~Confirmed), with identified parents James & John — first a daughter (b.~1900), then head of a 7-person household.
Age 40
b. ~1900
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Essex-County, Massachusetts |
| Surname | Monahan |
| Given Name | Mary Elizabeth |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 40 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Lawrence City |
| 1935 Residence (County) | Essex |
| Additional Details | |
| Occupation | Twister |
| Industry | Woolen Mill |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 800 |
| Highest Grade | No 6 |
| 1935 Residence | Same House |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Twister |
| Township / Ward | Lawrence City |
| Est. Birth Year | ~1900 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Celia Monahan | Daughter | — | 25 | ~1915 |
| Irene Monahan | Daughter | — | 24 | ~1916 |
| Mary Monahan | Spouse | — | 64 | ~1876 |
| John Monahan | Son | — | 30 | ~1910 |
| John Monahan | Head | — | 63 | ~1877 |
| Mary Monahan | Daughter | — | 40 | ~1900 |
| James Monahan | Son | — | 42 | ~1898 |
Census Appearances
1920
Essex, Massachusetts
Daughter, age 21
Essex, Massachusetts · implied b. ~1899 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | Mary E |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Occupation | Stitcher |
| Industry | Shoe Shop |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Essex, Massachusetts
Daughter, age 30
Essex, Massachusetts · implied b. ~1900 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Occupation | Worker |
| Industry | Lamp factory |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Essex-County, Massachusetts
Daughter, age 40
Essex-County, Massachusetts · implied b. ~1900 — 7 household members
| Surname | Monahan |
| Given Name | Mary Elizabeth |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 40 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Lawrence City |
| 1935 Residence (County) | Essex |
| Occupation | Twister |
| Industry | Woolen Mill |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 800 |
| Highest Grade | No 6 |
| 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 Monahan across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father James Monahan (~0.92 confidence) and father John Monahan (~0.92 confidence) and mother Margaret Monahan (~0.92 confidence) and mother Margaret Monahan (~0.92 confidence) and mother Mary Monahan (~0.92 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
James Monahan
b. ~1867
Source father
● Household
· direct · ~0.92
Father
John Monahan
b. ~1877
Source father
● Household
· direct · ~0.92
Mother
Margaret Monahan
b. ~1872
Source mother
● Household
· direct · ~0.92
Mother
Margaret Monahan
b. ~1873
Source mother
● Household
· direct · ~0.92
Mother
Mary Monahan
b. ~1876
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Monahan
Daughter · 1940 · age 40 · b. ~1900 · Massachusetts
★ You are viewing this record
Sibling
Celia Monahan
Sibling · 1940 · age 25
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
James Monahan
Sibling · 1940 · age 42
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Irene Monahan
Sibling · 1940 · age 24
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Monahan
Sibling · 1940 · age 30
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 — Essex-County, Massachusetts
Open full size
1940 US Federal Census — Essex-County, Massachusetts
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-01584-00471)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Lewis Morin | 64 | Head | Mule Spinner | Connecticut |
| 42 | Clara Morin | 59 | Wife | French Mender | England |
| 43 | Alfred Bolduc | 40 | Head | Janitor | Massachusetts |
| 44 | Rose Bolduc | 42 | Wife | — | New Hampshire |
| 45 | Alfred Jr. Bolduc | 16 | Son | — | Massachusetts |
| 46 | Chanel Bolduc | 11 | Son | — | Massachusetts |
| 47 | Edna Bolduc | 6 | Daughter | — | Massachusetts |
| 48 | John Frary | 39 | Head | Mill Hand | Massachusetts |
| 49 | Antoinette Frary | 34 | Wife | — | Massachusetts |
| 50 | Jacqueline Frary | 10 | Daughter | — | Massachusetts |
| 51 | Frank Frary | 2 | Son | — | Massachusetts |
| 52 | Beatrice J. Cummings | 37 | Head | Mender | New Hampshire |
| 53 | Narcisse Beaumier | 78 | Father | — | Canada |
| 54 | Philomene Beaumier | 77 | Mother | — | Canada |
| 55 | Joseph Allaire | 52 | Head | Route Foreman | Massachusetts |
| 56 | Louise Allaire | 49 | Wife | Forelady | Connecticut |
| 57 | Lorraine Allaire | 21 | Daughter | — | Massachusetts |
| 58 | Doris Allaire | 19 | Daughter | — | Massachusetts |
| 59 | Lucille Allaire | 11 | Daughter | — | Massachusetts |
| 61 | John Monahan | 63 | Head | Comber | Massachusetts |
| 62 | Mary Monahan | 64 | Wife | — | Massachusetts |
| 63 | Mary Elizabeth Monahan THIS PERSON | 40 | Daughter | Twister | Massachusetts |
| 64 | John Jr. Monahan | 30 | Son | Labourer | Massachusetts |
| 65 | Irene Monahan | 24 | Daughter | — | Massachusetts |
| 66 | Celia Monahan | 25 | Daughter | Clerk | Massachusetts |
| 67 | James Monahan | 42 | Son | Oiler | Massachusetts |
| 68 | Bernard J. Fallon | 46 | Head | Letter Carrier | Massachusetts |
| 69 | Sadie Fallon | 41 | Wife | Burler | Massachusetts |
| 70 | Francis J. Fallon | 15 | Son | — | Massachusetts |
| 71 | Bernard Jr. Fallon | 12 | Son | — | Massachusetts |
| 72 | Dorothy Fallon | 10 | Daughter | — | Massachusetts |
| 73 | James Fallon | 8 | Son | — | Massachusetts |
| 74 | Honoré Sirois | 53 | Head | Carpenter | Canada |
| 75 | Alvine Sirois | 50 | Wife | — | Canada |
| 76 | René Sirois | 21 | Son | Carpenters Helper | Massachusetts |
| 77 | Arthur Sirois | 20 | Son | — | Massachusetts |
| 78 | Lionel Sirois | 17 | Son | Carpenters Helper | Massachusetts |
| 79 | Albert Sirois | 15 | Son | — | Massachusetts |
| 80 | Isabelle Sirois | 14 | Daughter | — | Massachusetts |
Pedigree Summary
Mary + 4 siblings
Gen 1 · 5 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)