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Mary Monahan — 1930 US Census Record
Linked across censuses1930 United States Federal Census · Middlesex, Massachusetts
Our Model Tree links this Mary Monahan across the 1920 and 1930 US Censuses in Middlesex, Massachusetts (XGBoost, ~Confirmed) — first a daughter (b.~1916), then head of a 11-person household.
Age 14
b. ~1916
Female
Daughter
Born: Massachusetts
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | Middlesex, Massachusetts |
| Surname | Monahan |
| Given Name | Mary E. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Additional Details | |
| Occupation | Clerk |
| Industry | College |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Clerk |
| Township / Ward | Lowell City |
| Est. Birth Year | ~1916 |
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.
11 people recorded at the same address in the 1930 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| James Monahan | Son | — | 22 | ~1908 |
| William Monahan | Son | — | 25 | ~1905 |
| Delia Monahan | Daughter | — | 13 | ~1917 |
| Jeremiah Monahan | Head | — | 51 | ~1879 |
| Cornelius Monahan | Son | — | 9 | ~1921 |
| Jeremiah Monahan | Son | — | 23 | ~1907 |
| Rose Guyette | Spouse | — | 44 | ~1886 |
| Bridget Monahan | Spouse | — | 50 | ~1880 |
| John Monahan | Son | — | 15 | ~1915 |
| Mary Monahan | Daughter | — | 14 | ~1916 |
| Daniel Monahan | Son | — | 16 | ~1914 |
Census Appearances
1920
Middlesex, Massachusetts
Daughter, age 3
Middlesex, Massachusetts · implied b. ~1917 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | Mary L. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 3 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Middlesex, Massachusetts
Daughter, age 14
Middlesex, Massachusetts · implied b. ~1916 — 11 household members
| Surname | Monahan |
| Given Name | Mary E. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Clerk |
| Industry | College |
| Class of Worker | W |
| Can Read/Write | Yes |
| 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 (1920 and 1930) in Middlesex, Massachusetts, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Monahan
Daughter · 1930 · age 14 · b. ~1916 · Massachusetts
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Sibling
Daniel Monahan
Sibling · 1930 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Jeremiah Monahan
Sibling · 1930 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Monahan
Sibling · 1930 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
James Monahan
Sibling · 1930 · age 22
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Cornelius Monahan
Sibling · 1930 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Delia Monahan
Sibling · 1930 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
William Monahan
Sibling · 1930 · age 25
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
1930 US Federal Census — Middlesex, Massachusetts
Open full size
1930 US Federal Census — Middlesex, Massachusetts
Page Contents
50 people indexed on this census page (ia:1930:massachusettscensus00reel920:0529)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Hermine Dozois | 74 | Head | — | Canada |
| 2 | Eva Dozois | 50 | Daughter | Machine Girl | Canada |
| 3 | Emilia Dozois | 34 | Daughter | Inspector | Canada |
| 4 | Arthur Benoit | 16 | Son | Odd Boy | Massachusetts |
| 5 | Lillian Benoit | 13 | Daughter | — | Massachusetts |
| 6 | Arthur Guerin | 58 | Head | Health Visitor | Canada |
| 7 | Margaret Guerin | 40 | Wife | — | Massachusetts |
| 8 | Patrick F. Malloy | 36 | Head | Machinist | Massachusetts |
| 9 | Harriet Malloy | 36 | Wife | — | Massachusetts |
| 10 | Robert Malloy | 6 | Son | — | Massachusetts |
| 11 | Mary Malloy | 4 | Daughter | — | Massachusetts |
| 12 | Richard Malloy | 1 | Son | — | Massachusetts |
| 13 | Catherine Smith | 71 | Head | — | Massachusetts |
| 14 | John J. Smith | 48 | Son | Laborer | Massachusetts |
| 15 | Mary T. Smith | 45 | Daughter | Maid | Massachusetts |
| 16 | Catherine Gillick | 29 | Head | Clerk | Massachusetts |
| 17 | Alice Gillick | 27 | Sister | Binder | Massachusetts |
| 18 | Mary Gillick | 18 | Sister | Stitcher | Massachusetts |
| 19 | Joseph F. Gillick | 16 | Brother | Presser | Massachusetts |
| 20 | William Cloutier | 33 | Head | Sheet Worker | Canada |
| 21 | Alice Cloutier | 36 | Wife | — | Massachusetts |
| 22 | Jeremiah Monahan | 51 | Head | St. Fireman | Ireland |
| 23 | Bridget Monahan | 50 | Wife | — | Ireland |
| 24 | William J. Monahan | 25 | Son | Machinist | Massachusetts |
| 25 | Jeremiah J. Monahan | 23 | Son | Machinist | Massachusetts |
| 26 | James P. Monahan | 22 | Son | Helper | Massachusetts |
| 27 | Daniel P. Monahan | 16 | Son | Messenger | Massachusetts |
| 28 | John G. Monahan | 15 | Son | — | Massachusetts |
| 29 | Mary E. Monahan THIS PERSON | 14 | Daughter | Clerk | Massachusetts |
| 30 | Delia C. Monahan | 13 | Daughter | — | Massachusetts |
| 31 | Cornelius T. Monahan | 9 | Son | — | Massachusetts |
| 32 | Rose Guyette | 44 | Wife | — | Canada |
| 33 | Bormidas Guyette | 47 | Head | Edge Trimmer | Canada |
| 34 | Phillip Guyette | 11 | Son | — | Canada |
| 35 | Priscilla Guyette | 6 | Daughter | — | Massachusetts |
| 36 | John J. Sagger | 30 | Head | Laborer | Massachusetts |
| 37 | Alice Sagger | 4 | Daughter | — | Massachusetts |
| 38 | Raymond Sagger | 2 | Son | — | Massachusetts |
| 39 | James Sagger | 1 | Son | — | Massachusetts |
| 40 | Alice Sagger | 31 | Wife | — | Massachusetts |
| 41 | Ann Sagger | 3 | Daughter | — | Massachusetts |
| 42 | Mary M. O'Rourke | 49 | Head | — | Irish Free State |
| 43 | John O'Rourke | 15 | Son | — | Massachusetts |
| 44 | Margaret M. O'Rourke | 13 | Daughter | — | Massachusetts |
| 45 | James J. Mcdonough | 39 | Head | Drayman | Massachusetts |
| 46 | Alice V. H. Mcdonough | 35 | Wife | — | Massachusetts |
| 47 | Mary R. Mcdonough | 9 | Daughter | — | Massachusetts |
| 48 | Elizabeth J. Mcdonough | 6 | Daughter | — | Massachusetts |
| 49 | Patrick Cunningham | 50 | Head | Teamster | Irish Free State |
| 50 | Julia Cunningham | 54 | Wife | — | Irish Free State |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1930 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)