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John Mcdermott — 1940 US Census Record
Model Tree available1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this John Mcdermott across the 1910, 1920, 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed), with identified parents John & Thos — first a son (b.~1907), then head of a 5-person household.
Age 33
b. ~1907
Male
Son
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | McDermott |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 33 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Occupation | Clerical |
| Class of Worker | PW |
| Hours Worked | 52 |
| Income (1939) | 0 |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Clerical |
| Township / Ward | Boston City |
| 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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Grace Mcdermott | Daughter | — | 17 | ~1923 |
| Mary Mcdermott | Head | — | 55 | ~1885 |
| John Mcdermott | Son | — | 33 | ~1907 |
| William Mcdermott | Son | — | 28 | ~1912 |
| Charles Mcdermott | Son | — | 19 | ~1921 |
Census Appearances
1910
Suffolk, Massachusetts
Son, age 3
Suffolk, Massachusetts · implied b. ~1907 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDermott |
| Given Name | John H. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 3 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1920
Suffolk, Massachusetts
Son, age 13
Suffolk, Massachusetts · implied b. ~1907 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDermott |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Suffolk, Massachusetts
Son, age 23
Suffolk, Massachusetts · implied b. ~1907 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDermott |
| Given Name | John J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 23 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Occupation | Clerk |
| Industry | Office |
| Class of Worker | W |
| Can Read/Write | Yes |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Son, age 33
Suffolk-County, Massachusetts · implied b. ~1907 — 5 household members
| Surname | McDermott |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 33 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Occupation | Clerical |
| Class of Worker | PW |
| Hours Worked | 52 |
| Income (1939) | 0 |
| Highest Grade | No 8 |
| 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 Mcdermott across 4 US Census years (1910, 1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father John Mcdermott (~0.92 confidence) and father Thos Mcdermott (~0.92 confidence) and mother Jane Mcdermott (~0.92 confidence) and mother Mary Mcdermott (~0.92 confidence) and mother Mary Mcdermott (~0.92 confidence) and father John Mcdermott (~0.92 confidence) and mother Mildred Mcdermott (~0.92 confidence). The pedigree spans 1 generation with 7 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
John Mcdermott
b. ~1879
Source father
● Household
· direct · ~0.92
Father
Thos Mcdermott
b. ~1879
Source father
● Household
· direct · ~0.92
Mother
Jane Mcdermott
b. ~1880
Source mother
● Household
· direct · ~0.92
Mother
Mary Mcdermott
b. ~1885
Source mother
● Household
· direct · ~0.92
Mother
Mary Mcdermott
b. ~1885
Source mother
● Household
· direct · ~0.92
Father
John Mcdermott
b. ~1888
Source father
● Household
· direct · ~0.92
Mother
Mildred Mcdermott
b. ~1890
Source mother
● Household
· direct · ~0.92
This person
Anchor record
John Mcdermott
Son · 1940 · age 33 · b. ~1907 · Massachusetts
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Sibling
Grace Mcdermott
Sibling · 1940 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Charles Mcdermott
Sibling · 1940 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
William Mcdermott
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 — 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-t0627-01659-00118)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Houghton Cornelius | 62 | Head | Wharfman | Northern Ireland |
| 2 | Elizabeth Houghton | 61 | Wife | — | Northern Ireland |
| 3 | Fedele Piannelle | 63 | Head | Custodian | Italy |
| 4 | Virginia Piannelle | 53 | Wife | — | Italy |
| 5 | Anna Piannelle | 30 | Daughter | Bookkeeper | Massachusetts |
| 6 | Joseph Piannelle | 28 | Son | Laborer | Massachusetts |
| 7 | John Piannelle | 24 | Son | Clerk | Massachusetts |
| 8 | Christine Piannelle | 18 | Daughter | — | Massachusetts |
| 9 | Francis Piannelle | 16 | Son | — | Massachusetts |
| 10 | Catherine Harrington | 47 | Head | — | Eire |
| 11 | Frank Harrington | 26 | Son | Electrician | Massachusetts |
| 12 | Mary Harrington | 24 | Daughter | File Clerk | Massachusetts |
| 13 | Catherine Harrington | 21 | Daughter | — | Massachusetts |
| 14 | William Harrington | 19 | Son | File Clerk | Massachusetts |
| 15 | Edward Harrington | 14 | Son | — | Massachusetts |
| 16 | Elizabeth Harrington | 12 | Daughter | — | Massachusetts |
| 17 | Timothy P. Murphy | 59 | Head | Supply Clerk | Massachusetts |
| 18 | Mary F. Murphy | 58 | Wife | — | Massachusetts |
| 19 | Francis X. Murphy | 26 | Son | School Teacher | Massachusetts |
| 20 | Paul J. Murphy | 22 | Son | — | Massachusetts |
| 21 | Mary J. Murphy | 20 | Daughter | — | Massachusetts |
| 22 | Mary E. Mcdermott | 69 | Head | Binder | Massachusetts |
| 23 | Annie J. Mcdermott | 65 | Sister | Book Binder | Massachusetts |
| 24 | Elizabeth J. Mcdermott | 63 | Sister | — | Massachusetts |
| 25 | John J. Mcdermott | 24 | Nephew | Laborer | Massachusetts |
| 26 | Mary E. Mcdermott | 21 | Niece | Accountant | Massachusetts |
| 27 | Mary Mcdermott | 55 | Head | — | Massachusetts |
| 28 | John Mcdermott THIS PERSON | 33 | Son | Clerical | Massachusetts |
| 29 | William W. Mcdermott | 28 | Son | Accountant | Massachusetts |
| 30 | Charles V. Mcdermott | 19 | Son | Laborer | Massachusetts |
| 31 | Grace F. Mcdermott | 17 | Daughter | — | Massachusetts |
| 32 | Charles S. Healey | 57 | Head | Fireman | Massachusetts |
| 33 | Josephine A. Healey | 46 | Wife | — | Massachusetts |
| 34 | Charles S. Jr. Healey | 19 | Son | Auto Mechanic | Massachusetts |
| 35 | Marie Healey | 17 | Daughter | — | Massachusetts |
| 36 | Arnold Healey | 15 | Son | — | Massachusetts |
| 37 | Paul Healey | 9 | Son | — | Massachusetts |
| 38 | Robert Healey | 8 | Son | — | Massachusetts |
| 39 | Claire Healey | 6 | Daughter | — | Massachusetts |
| 40 | Isabel Harris | 69 | Mother in law | — | Maine |
Pedigree Summary
John + 3 siblings
Gen 1 · 7 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)