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Mary Leahy — 1930 US Census Record
Linked across censuses1930 United States Federal Census · Middlesex, Massachusetts
Our Model Tree links this Mary Leahy across the 1920 and 1930 US Censuses in Middlesex, Massachusetts (XGBoost, ~Confirmed) — first a head (b.~1875), then head of a 4-person household.
Age 55
b. ~1875
Female
Head
Born: Massachusetts
Widowed
1930 Census Record Details
| Census Year | 1930 |
| Location | Middlesex, Massachusetts |
| Surname | Leahy |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 55 |
| Marital Status | Widowed |
| Birthplace | Massachusetts |
| Age at First Marriage | 21 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Additional Details | |
| Occupation | Operator |
| Industry | Cotton Mill |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | R |
| Home Value / Rent | 25.00 |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Operator |
| Township / Ward | City Of Lowell |
| Est. Birth Year | ~1875 |
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.
4 people recorded at the same address in the 1930 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Agnes Leahy | Spouse | — | 33 | ~1897 |
| Harry Leahy | Son | — | 16 | ~1914 |
| William Leahy | Son | — | 8 | ~1922 |
| Mary Leahy | Head | — | 55 | ~1875 |
Census Appearances
1920
Middlesex, Massachusetts
Daughter, age 45
Middlesex, Massachusetts · implied b. ~1875 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leahy |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 45 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Middlesex, Massachusetts
Head, age 55
Middlesex, Massachusetts · implied b. ~1875 — 4 household members
| Surname | Leahy |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 55 |
| Marital Status | Widowed |
| Birthplace | Massachusetts |
| Age at First Marriage | 21 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Operator |
| Industry | Cotton Mill |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | R |
| Home Value / Rent | 25.00 |
| 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 Leahy across 2 US Census years (1920 and 1930) in Middlesex, Massachusetts, using XGBoost record linkage.
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This person
Anchor record
Mary Leahy
Head · 1930 · age 55 · b. ~1875 · Massachusetts
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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:massachusettscensus00reel921:0603)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Margaret Mcpartland | 36 | Head | Saleslady | Massachusetts |
| 2 | Hall | 42 | Head | Asst. Supt. | Massachusetts |
| 3 | Margaret Hall | 41 | Wife | — | Massachusetts |
| 4 | James Brown | 50 | Boarder | — | Massachusetts |
| 5 | Timothy O'Neil | 39 | Head | Beltman | Massachusetts |
| 6 | Margaret O'Neil | 33 | Wife | Beltman | Irish Free State |
| 7 | Elizabeth O'Neil | 11 | Daughter | — | Massachusetts |
| 8 | John O'Neil | 7 | Son | — | Massachusetts |
| 9 | Paul O'Neil | 3 | Son | — | Massachusetts |
| 10 | Mary Ford | 70 | Mother-in-law | — | Irish Free State |
| 11 | Arthur G. Lawson | 40 | Head | Watchman | Massachusetts |
| 12 | Elizabeth Lawson | 51 | Wife | — | Massachusetts |
| 13 | Charles W. Masterson | 76 | Roomer | Soap Maker | Maine |
| 14 | Mary Gaynor | 71 | Head | — | Irish Free State |
| 15 | George Gaynor | 44 | Son | Knitter | Massachusetts |
| 16 | Maddie Gaynor | 36 | Dept. Store | Buyer | Connecticut |
| 17 | Michael J. Fahey | 51 | Head | Fireman | Massachusetts |
| 18 | Emma L. Fahey | 37 | Wife | — | Massachusetts |
| 19 | Mary D. Fahey | 6 | Daughter | — | Massachusetts |
| 20 | Michael Fahey | 4 | Son | — | Massachusetts |
| 21 | Emma L. Fahey | 2 | Daughter | — | Massachusetts |
| 22 | Thomas Manning | 58 | Head | Laborer | Irish Free State |
| 23 | Helen Manning | 55 | Wife | — | Irish Free State |
| 24 | John Manning | 24 | Son | Printer | Massachusetts |
| 25 | Katherine Manning | 20 | Daughter | Operator | Massachusetts |
| 26 | Henry Dowd | 26 | Brother-in-law | Clerk | Massachusetts |
| 27 | Mary E. Dowd | 26 | Sister-in-law | — | Massachusetts |
| 28 | John Manning | 28 | Nephew | Cutter | Massachusetts |
| 29 | Helen Manning | 21 | Niece | Examiner | Massachusetts |
| 30 | Mary Leahy THIS PERSON | 55 | Head | Operator | Massachusetts |
| 31 | Agnes Leahy | 33 | Wife | — | Massachusetts |
| 32 | Harry W. Leahy | 16 | Son | — | Massachusetts |
| 33 | William Leahy | 8 | Son | — | Massachusetts |
| 34 | Stephen Howillette | 49 | Head | Knitter | Maine |
| 35 | Delia Howillette | 48 | Wife | — | Canada French |
| 36 | William Howillette | 25 | Son | Clerk | Massachusetts |
| 37 | Eva Howillette | 18 | Daughter | Knitter | Massachusetts |
| 38 | Ernest Howillette | 13 | Son | — | Massachusetts |
| 39 | Maurice Howillette | 12 | Son | — | Massachusetts |
| 40 | Leo Howillette | 10 | Son | — | Massachusetts |
| 41 | George Howillette | 8 | Son | — | Massachusetts |
| 42 | Edward Lynch | 43 | Head | Embalmer | Massachusetts |
| 43 | Julia Lynch | 43 | Wife | — | Canada English |
| 44 | Robert Lynch | 16 | Son | — | Massachusetts |
| 45 | Thomas J. Lynch | 15 | Son | — | Massachusetts |
| 46 | Patricia Lynch | 13 | Daughter | — | Massachusetts |
| 47 | Walter Lynch | 11 | Son | — | Massachusetts |
| 48 | Edward J. Lynch | 9 | Son | — | Massachusetts |
| 49 | Arthur F. Lynch | 38 | Brother | Teamster | Massachusetts |
| 50 | Harold Lynch | 30 | Brother | — | Massachusetts |
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)