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Mary Mckay — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this Mary Mckay across the 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed) — first a daughter (b.~1930), then head of a 7-person household.
Age 10
b. ~1930
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | McKay |
| Given Name | Mary L |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Highest Grade | No 5 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Township / Ward | Boston |
| Est. Birth Year | ~1930 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Mckay | Head | — | 37 | ~1903 |
| Elizabeth Mckay | Daughter | — | 4 | ~1936 |
| Florence Mckay | Daughter | — | 12 | ~1928 |
| Mary Mckay | Daughter | — | 10 | ~1930 |
| Janet Mckay | Daughter | — | 2 | ~1938 |
| Lewis Mckay | Son | — | 15 | ~1925 |
| Robert Mckay | Son | — | 14 | ~1926 |
Census Appearances
1930
Suffolk, Massachusetts
Daughter, age
Suffolk, Massachusetts · implied b. ~1930 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McKay |
| Given Name | Mary L. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 0 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Massachusetts |
| Can Read/Write | No |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Daughter, age 10
Suffolk-County, Massachusetts · implied b. ~1930 — 7 household members
| Surname | McKay |
| Given Name | Mary L |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Highest Grade | No 5 |
| 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 Mary Mckay across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mckay
Daughter · 1940 · age 10 · b. ~1930 · Massachusetts
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Sibling
Florence Mckay
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Robert Mckay
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Janet Mckay
Sibling · 1940 · age 2
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Elizabeth Mckay
Sibling · 1940 · age 4
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Lewis Mckay
Sibling · 1940 · age 15
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-t0627-01664-00553)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Mary E Marston | 67 | Wife | — | Massachusetts |
| 42 | Charles T Jr Marston | 30 | Son | Clerk | Massachusetts |
| 43 | Mozelle Marston | 19 | Daughter | Bookkeeper | Massachusetts |
| 44 | Charles T Iii Marston | 8 | Grandchild | — | Massachusetts |
| 45 | Lorraine Marston | 4 | Grandchild | — | Massachusetts |
| 46 | Raymond Flanagan | 37 | Nephew | Electrician | Massachusetts |
| 47 | Mary Murphy | 27 | Cousin | Candy Roller | Massachusetts |
| 48 | James F Mccaron | 66 | Head | Clerk | Massachusetts |
| 49 | Helen C Mccaron | 64 | Sister | Housework | Massachusetts |
| 50 | Charles A Mccaron | 62 | Brother | Packer | Massachusetts |
| 51 | Agnes Devereaux | 41 | Head | Housework | Nova Scotia |
| 52 | Ralph Devereaux | 45 | Nephew | Steamfitter | Maine |
| 53 | John Muir | 35 | Head | Laborer | Eire |
| 54 | Rita Muir | 31 | Wife | Housework | Eire |
| 55 | Charles Hendrick | 79 | Head | Retired | New York |
| 56 | Margaret Dickie | 60 | Head | Housework | Eire |
| 57 | Annie Mcnamara | 77 | Sister | Housework | Eire |
| 58 | Emile Patenaude | 46 | Head | Shoer | New Hampshire |
| 59 | Mary C Patenaude | 45 | Wife | Housework | Massachusetts |
| 60 | Francis E Patenaude | 13 | Son | — | Massachusetts |
| 61 | Timothy Driscoll | 54 | Head | Chauffeur | Massachusetts |
| 62 | Catherine Driscoll | 44 | Wife | Housework | Nova Scotia |
| 63 | John Driscoll | 22 | Son | Kitchen Worker | Massachusetts |
| 64 | Dorothy A Driscoll | 18 | Daughter | Waitress | Massachusetts |
| 65 | Phyllis L Driscoll | 16 | Daughter | — | Massachusetts |
| 66 | Rita C Driscoll | 14 | Daughter | — | Massachusetts |
| 67 | Robert Driscoll | 10 | Son | — | Massachusetts |
| 68 | Mary Mckay | 37 | Head | Housework | Massachusetts |
| 69 | Lewis A Mckay | 15 | Son | — | Massachusetts |
| 70 | Robert J Mckay | 14 | Son | — | Massachusetts |
| 71 | Florence T Mckay | 12 | Daughter | — | Massachusetts |
| 72 | Mary L Mckay THIS PERSON | 10 | Daughter | — | Massachusetts |
| 73 | Elizabeth A Mckay | 4 | Daughter | — | Massachusetts |
| 74 | Janet A Mckay | 2 | Daughter | — | Massachusetts |
| 75 | Arthur B Wood | 25 | Head | None | Nova Scotia |
| 76 | Gertrude B Wood | 21 | Wife | Housework | Massachusetts |
| 77 | Patricia Wood | 3 | Daughter | — | Massachusetts |
| 78 | Robert Wood | 2 | Son | — | Massachusetts |
| 79 | Richard Wood | 0 | Son | — | Massachusetts |
| 80 | Maria Logan | 56 | Head | Housework | Massachusetts |
Related Census Records
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)