JC
John Cahill — 1940 US Census Record
Model Tree available1940 United States Federal Census · Middlesex-County, Massachusetts
Our Model Tree links this John Cahill across the 1920, 1930 and 1940 US Censuses in Middlesex-County, Massachusetts (XGBoost, ~Confirmed), with identified parents Timothy & Helen — first a head (b.~1907), then head of a 3-person household.
Age 33
b. ~1907
Male
Head
Born: Rhode Island
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Middlesex-County, Massachusetts |
| Surname | Cahill |
| Given Name | John T. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 33 |
| Marital Status | Married |
| Birthplace | Rhode Island |
| 1935 Residence (City) | Somerville |
| 1935 Residence (County) | Middlesex |
| Additional Details | |
| Occupation | Shipping clerk |
| Industry | Soap Mfg. |
| Class of Worker | PW |
| Hours Worked | 35 |
| Income (1939) | 1664 |
| Highest Grade | H 3 |
| 1935 Residence | Same place |
| Birth State | Rhode Island |
| Birth Country | United States |
| Birthplace (normalized) | rhode island |
| Occupation | Shipping Clerk |
| Township / Ward | Somerville |
| Est. Birth Year | ~1907 |
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.
3 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| John Cahill | Head | — | 33 | ~1907 |
| Gladys Cahill | Spouse | — | 33 | ~1907 |
| Marilyn Cahill | Daughter | — | 3 | ~1937 |
Census Appearances
1920
Middlesex, Massachusetts
Son, age 13
Middlesex, Massachusetts · implied b. ~1907 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cahill |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Rhode Island |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Rhode Island |
| Birth Country | United States |
| Birthplace (normalized) | rhode island |
1930
Middlesex, Massachusetts
Son, age 24
Middlesex, Massachusetts · implied b. ~1906 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cahill |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 24 |
| Marital Status | Single |
| Birthplace | Rhode Island |
| Father's Birthplace | Ireland (F.S.) |
| Mother's Birthplace | Ireland (F.S.) |
| Occupation | Shipper |
| Industry | Soap |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Rhode Island |
| Birth Country | United States |
| Birthplace (normalized) | rhode island |
1940
Middlesex-County, Massachusetts
Head, age 33
Middlesex-County, Massachusetts · implied b. ~1907 — 3 household members
| Surname | Cahill |
| Given Name | John T. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 33 |
| Marital Status | Married |
| Birthplace | Rhode Island |
| 1935 Residence (City) | Somerville |
| 1935 Residence (County) | Middlesex |
| Occupation | Shipping clerk |
| Industry | Soap Mfg. |
| Class of Worker | PW |
| Hours Worked | 35 |
| Income (1939) | 1664 |
| Highest Grade | H 3 |
| 1935 Residence | Same place |
| Birth State | Rhode Island |
| Birth Country | United States |
| Birthplace (normalized) | rhode island |
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 Cahill across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Timothy Cahill (~0.92 confidence) and mother Helen Cahill (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Timothy Cahill
b. ~1880
Source father
● Household
· direct · ~0.92
Mother
Helen Cahill
b. ~1882
Source mother
● Household
· direct · ~0.92
This person
Anchor record
John Cahill
Head · 1940 · age 33 · b. ~1907 · Massachusetts
★ You are viewing this record
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-t0627-01705-00451)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Louise M. Dinschel | 4 | Daughter | — | Connecticut |
| 2 | Louella J. Dinschel | 3 | Daughter | — | Connecticut |
| 3 | George W. Dinschel | 1 | Son | — | Massachusetts |
| 4 | George O. Whitnell | 72 | Head | — | England |
| 5 | Jennie Whitnell | 66 | Wife | — | England |
| 6 | James Whitnell | 28 | Son | State Laborer | England |
| 7 | John T. Cahill THIS PERSON | 33 | Head | Shipping Clerk | Rhode Island |
| 8 | Gladys Cahill | 33 | Wife | — | Massachusetts |
| 9 | Marilyn Cahill | 3 | Daughter | — | Massachusetts |
| 10 | Joshua Cleaves | 66 | Head | Police Officer | Canada-English |
| 11 | Rose Cleaves | 61 | Wife | — | England |
| 12 | Leslie Cleaves | 33 | Son | Canvasser | Massachusetts |
| 13 | James Looney | 44 | Head | Senior Clerk | Massachusetts |
| 14 | Ann Looney | 39 | Wife | — | Eire |
| 15 | James Looney | 5 | Son | — | Massachusetts |
| 16 | John Looney | 3 | Son | — | Massachusetts |
| 17 | John Reidy | 39 | Head | Trucking | Massachusetts |
| 18 | Elizabeth Reidy | 32 | Wife | — | Massachusetts |
| 19 | John Reidy | 7 | Son | — | Massachusetts |
| 20 | Cynthia Reidy | 6 | Daughter | — | Massachusetts |
| 21 | Ursula Reidy | 5 | Daughter | — | Massachusetts |
| 22 | John Volpe | 37 | Head | Insurance Agent | Italy |
| 23 | Emily Volpe | 38 | Wife | — | Massachusetts |
| 24 | Leonard Volpe | 13 | Son | — | Massachusetts |
| 25 | Ernest Volpe | 11 | Son | — | Massachusetts |
| 26 | Rose Volpe | 3 | Daughter | — | Massachusetts |
| 27 | David Hatfield | 28 | Head | Glass Grinder | Massachusetts |
| 28 | Margaret Hatfield | 24 | Wife | — | Massachusetts |
| 29 | Marion Hatfield | 3 | Daughter | — | Massachusetts |
| 30 | David Hatfield | 0 | Son | — | Massachusetts |
| 31 | John Forte | 32 | Head | Post Office Clerk | Massachusetts |
| 32 | Antoinette Forte | 29 | Wife | — | New York |
| 33 | John Forte | 8 | Son | — | Massachusetts |
| 34 | James Forte | 3 | Son | — | Massachusetts |
| 35 | Anthony Perniello | 45 | Head | Real Estate Operator | Massachusetts |
| 36 | Florence Perniello | 38 | Wife | — | Massachusetts |
| 37 | Edward Rose | 37 | Head | Hardware Dealer | Massachusetts |
| 38 | Margaret Rose | 32 | Wife | — | Massachusetts |
| 39 | Edward Rose | 3 | Son | — | Massachusetts |
| 40 | Robert Rose | 1 | Son | — | Massachusetts |
Pedigree Summary
John
Gen 1 · 2 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)