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Mary Monahan — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this Mary Monahan across the 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed) — first a daughter (b.~1926), then head of a 8-person household.
Age 14
b. ~1926
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | Monahan |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Highest Grade | H 1 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Township / Ward | Boston |
| Est. Birth Year | ~1926 |
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.
8 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Dorothy Monahan | Daughter | — | 4 | ~1936 |
| Joseph Monahan | Son | — | 16 | ~1924 |
| Elizabeth Monahan | Daughter | — | 18 | ~1922 |
| Helen Monahan | Daughter | — | 10 | ~1930 |
| Ann Monahan | Daughter | — | 11 | ~1929 |
| Mary Monahan | Daughter | — | 14 | ~1926 |
| Ada Monahan | Spouse | — | 48 | ~1892 |
| John Monahan | Son | — | 8 | ~1932 |
Census Appearances
1930
Suffolk, Massachusetts
Daughter, age 4
Suffolk, Massachusetts · implied b. ~1926 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Daughter, age 14
Suffolk-County, Massachusetts · implied b. ~1926 — 8 household members
| Surname | Monahan |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Highest Grade | H 1 |
| 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 Monahan across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Monahan
Daughter · 1940 · age 14 · b. ~1926 · Massachusetts
★ You are viewing this record
Sibling
Joseph Monahan
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Monahan
Sibling · 1940 · age 8
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ann Monahan
Sibling · 1940 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Elizabeth Monahan
Sibling · 1940 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Dorothy Monahan
Sibling · 1940 · age 4
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Helen Monahan
Sibling · 1940 · age 10
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 — Suffolk-County, Massachusetts
Open full size
1940 US Federal Census — Suffolk-County, Massachusetts
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01674-00714)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Ada Monahan | 48 | Wife | — | Massachusetts |
| 42 | Elizabeth Monahan | 18 | Daughter | — | Massachusetts |
| 43 | Joseph Monahan | 16 | Son | — | Massachusetts |
| 44 | Mary Monahan THIS PERSON | 14 | Daughter | — | Massachusetts |
| 45 | Ann Monahan | 11 | Daughter | — | Massachusetts |
| 46 | Helen Monahan | 10 | Daughter | — | Massachusetts |
| 47 | John Monahan | 8 | Son | — | Massachusetts |
| 48 | Dorothy Monahan | 4 | Daughter | — | Massachusetts |
| 49 | John Shooshanian | 46 | Head | Storekeeper | Turkey |
| 50 | Alice Shooshanian | 35 | Wife | — | Turkey |
| 51 | Edward Shooshanian | 12 | Son | — | Massachusetts |
| 52 | Clara Shooshanian | 10 | Daughter | — | Massachusetts |
| 53 | Agnes Shooshanian | 57 | Mother | — | Turkey |
| 54 | Margaret Carelli | 46 | Head | Spinner | Italy |
| 55 | Rose Carelli | 25 | Daughter | Librarian | Massachusetts |
| 56 | Eleanor Carelli | 22 | Daughter | — | Massachusetts |
| 57 | Leonora Carelli | 15 | Daughter | — | Massachusetts |
| 58 | William Carelli | 11 | Son | — | Massachusetts |
| 59 | Vernon W. Connelly | 62 | Head | Machinist | Vermont |
| 60 | Mabel Connelly | 56 | Wife | — | Vermont |
| 61 | Marjorie Murphy | 25 | Boarder | Sorter | Massachusetts |
| 62 | Helen Carelli | 22 | Boarder | Manager | Maine |
| 63 | Gino Ricci | 61 | Head | — | Italy |
| 64 | Christina Ricci | 38 | Daughter | Hostess | Massachusetts |
| 65 | Mary Ricci | 25 | Daughter | Waitress | Massachusetts |
| 66 | Catherine Ricci | 20 | Daughter | Hostess | Massachusetts |
| 67 | Joseph Ricci | 17 | Son | — | Massachusetts |
| 68 | Samuel Bova | 59 | Head | Fisherman | Italy |
| 69 | Nellie Bova | 30 | Daughter | Waitress | Massachusetts |
| 70 | Catherine Bova | 8 | Daughter | — | Massachusetts |
| 71 | Vincent Walsh | 29 | Head | Teacher | Massachusetts |
| 72 | Mike Rossi | 72 | Head | — | Ireland |
| 73 | Mary Waters | 75 | Aunt | — | Ireland |
| 74 | Edith Cunningham | 63 | Boarder | Select | Ireland |
| 75 | Michael Noonan | 23 | Boarder | Helper | Ireland |
| 76 | Herbert Ochs | 52 | Boarder | Laborer | Massachusetts |
| 77 | John Holland | 42 | Boarder | Electrician | Massachusetts |
| 78 | John Mulhern | 58 | Boarder | Electrician | Massachusetts |
| 79 | Carl Jensen | 58 | Head | Watchman | Maine |
| 80 | Edna M. Jensen | 58 | Wife | — | Maine |
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)