JL
John Leary — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Middlesex-County, Massachusetts
Our Model Tree links this John Leary across the 1930 and 1940 US Censuses in Middlesex-County, Massachusetts (XGBoost, ~Confirmed) — first a son (b.~1910), then head of a 8-person household.
Age 30
b. ~1910
Male
Son
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Middlesex-County, Massachusetts |
| Surname | Leary |
| Given Name | John J |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Lawrence (pt) |
| 1935 Residence (County) | Middlesex |
| Additional Details | |
| Occupation | Clerk Meat Store |
| Industry | Retail Meat Store |
| Class of Worker | PW |
| Hours Worked | 44 |
| Income (1939) | 1400 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same Place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Clerk Meat Store |
| Township / Ward | Lawrence Pt |
| Est. Birth Year | ~1910 |
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 John | Age | Birth yr |
|---|---|---|---|---|
| Elizabeth Leary | Daughter | — | 14 | ~1926 |
| Anne Leary | Daughter | — | 19 | ~1921 |
| John Leary | Son | — | 30 | ~1910 |
| Rita Leary | Daughter | — | 21 | ~1919 |
| Mary Leary | Daughter | — | 28 | ~1912 |
| Thomas Leary | Head | — | 60 | ~1880 |
| Mary Leary | Spouse | — | 60 | ~1880 |
| Thomas Leary | Son | — | 27 | ~1913 |
Census Appearances
1930
Suffolk, Massachusetts
Son, age 20
Suffolk, Massachusetts · implied b. ~1910 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leary |
| Given Name | John J |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Massachusetts |
| Can Read/Write | Yes |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Middlesex-County, Massachusetts
Son, age 30
Middlesex-County, Massachusetts · implied b. ~1910 — 8 household members
| Surname | Leary |
| Given Name | John J |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Lawrence (pt) |
| 1935 Residence (County) | Middlesex |
| Occupation | Clerk Meat Store |
| Industry | Retail Meat Store |
| Class of Worker | PW |
| Hours Worked | 44 |
| Income (1939) | 1400 |
| Highest Grade | Hs 4 |
| 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 John Leary across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Leary
Son · 1940 · age 30 · b. ~1910 · Massachusetts
★ You are viewing this record
Sibling
Thomas Leary
Sibling · 1940 · age 27
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Anne Leary
Sibling · 1940 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Rita Leary
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Elizabeth Leary
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mary Leary
Sibling · 1940 · age 28
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-t0627-01705-00623)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Phyllis Robinson | 21 | Daughter | — | Massachusetts |
| 42 | Rosamond Robinson | 18 | Daughter | — | Massachusetts |
| 43 | Francis Johnson | 44 | Head | Elevator Inspector | Massachusetts |
| 44 | Catherine Johnson | 43 | Wife | Bank Clerk | New York |
| 45 | Geraldine Johnson | 21 | Daughter | Bank Clerk | Massachusetts |
| 46 | Paul A Johnson | 15 | Son | — | Massachusetts |
| 47 | John J Caleford | 45 | Head | Laborer | Ireland |
| 48 | Catherine Caleford | 35 | Wife | — | Ireland |
| 49 | Mary Caleford | 4 | Daughter | — | Massachusetts |
| 50 | Abraham Young | 42 | Head | — | Maine |
| 51 | Thelma D Young | 34 | Wife | — | Maine |
| 52 | Willis A Young | 3 | Son | — | Massachusetts |
| 53 | Clarence A Young | 1 | Son | — | Massachusetts |
| 54 | Adelaide Hannon | 60 | Head | — | Maine |
| 55 | Manuel Baptiste | 61 | Lodger | — | Portugal |
| 56 | Mihran M Lazekian | 42 | Head | Candy Salesman | Turkey |
| 57 | Marboure Lazekian | 35 | Wife | — | Turkey |
| 58 | Mary Lazekian | 12 | Daughter | — | Massachusetts |
| 59 | Kaspar M Lazekian | 11 | Son | — | Massachusetts |
| 60 | Astor Lazekian | 5 | Son | — | Massachusetts |
| 61 | Muriel Robie | 45 | Head | Drug Store Clerk | Vermont |
| 62 | Christine V Robie | 22 | Daughter | Clerk Card Index | Massachusetts |
| 63 | Nellie Demmory | 70 | Mother | — | English Canada |
| 64 | Horand Haboosian | 45 | Head | Mens Tailor | Turkey |
| 65 | Rose Haboosian | 34 | Wife | Dressmaking | Connecticut |
| 66 | Shant Haboosian | 13 | Son | — | Massachusetts |
| 67 | Antad Haboosian | 6 | Daughter | — | Massachusetts |
| 68 | John J Duffy | 62 | Head | Tailor | Ireland |
| 69 | Jane F Duffy | 70 | Wife | Drug Store Clerk | Ireland |
| 70 | Thomas Leary | 60 | Head | Curing Meat | Eire |
| 71 | Mary Leary | 60 | Wife | — | Ireland |
| 72 | John J Leary THIS PERSON | 30 | Son | Clerk Meat Store | Massachusetts |
| 73 | Mary J Leary | 28 | Daughter | Stenographer | Massachusetts |
| 74 | Thomas P Leary | 27 | Son | Clerk Meat Store | Massachusetts |
| 75 | Rita C Leary | 21 | Daughter | Bookkeeper | Massachusetts |
| 76 | Anne T Leary | 19 | Daughter | — | Massachusetts |
| 77 | Elizabeth A Leary | 14 | Daughter | — | Massachusetts |
| 78 | Patrick Sullivan | 36 | Head | Bodywork Restaurant | Eire |
| 79 | Eleanore Sullivan | 36 | Wife | Restaurant Bartender | Eire |
| 80 | Allison Tumblin | 44 | Head | Steel Worker | English Canada |
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)