MG
Mary Griffin — 1940 US Census Record
Model Tree available1940 United States Federal Census · Middlesex-County, Massachusetts
Our Model Tree links this Mary Griffin across the 1920, 1930 and 1940 US Censuses in Middlesex-County, Massachusetts (XGBoost, ~Confirmed), with identified parents Ellen & Patrick — first a daughter (b.~1919), then head of a 5-person household.
Age 21
b. ~1919
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Middlesex-County, Massachusetts |
| Surname | Griffin |
| Given Name | Mary E |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Medford City |
| 1935 Residence (County) | Middlesex |
| Additional Details | |
| Occupation | Filing Clerk |
| Industry | Savings Bank |
| Class of Worker | PW |
| Hours Worked | 35 |
| Income (1939) | 279 |
| Highest Grade | H-4 |
| 1935 Residence | Same Place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Filing Clerk |
| Township / Ward | Medford City |
| Est. Birth Year | ~1919 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Griffin | Daughter | — | 21 | ~1919 |
| Patrick Griffin | Head | — | 57 | ~1883 |
| Gerald Griffin | Son | — | 25 | ~1915 |
| Patrick Griffin | Son | — | 15 | ~1925 |
| Ellen Griffin | Spouse | — | 58 | ~1882 |
Census Appearances
1920
Middlesex, Massachusetts
Daughter, age 1
Middlesex, Massachusetts · implied b. ~1919 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Griffin |
| Given Name | Mary E. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Middlesex, Massachusetts
Daughter, age 11
Middlesex, Massachusetts · implied b. ~1919 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Griffin |
| Given Name | Mary E. |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Middlesex-County, Massachusetts
Daughter, age 21
Middlesex-County, Massachusetts · implied b. ~1919 — 5 household members
| Surname | Griffin |
| Given Name | Mary E |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Medford City |
| 1935 Residence (County) | Middlesex |
| Occupation | Filing Clerk |
| Industry | Savings Bank |
| Class of Worker | PW |
| Hours Worked | 35 |
| Income (1939) | 279 |
| Highest Grade | H-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 Mary Griffin across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: mother Ellen Griffin (~0.92 confidence) and father Patrick Griffin (~0.92 confidence) and mother Ellen Griffin (~0.92 confidence) and father Patrick Griffin (~0.92 confidence). The pedigree spans 1 generation with 4 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Mother
Ellen Griffin
b. ~1881
Source mother
● Household
· direct · ~0.92
Father
Patrick Griffin
b. ~1882
Source father
● Household
· direct · ~0.92
Mother
Ellen Griffin
b. ~1882
Source mother
● Household
· direct · ~0.92
Father
Patrick Griffin
b. ~1883
Source father
● Household
· direct · ~0.92
This person
Anchor record
Mary Griffin
Daughter · 1940 · age 21 · b. ~1919 · Massachusetts
★ You are viewing this record
Sibling
Gerald Griffin
Sibling · 1940 · age 25
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Patrick Griffin
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 — 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-t0627-01611-00260)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Warren F Smith | 41 | Head | Laborer | Massachusetts |
| 2 | Helen E Smith | 39 | Wife | — | Massachusetts |
| 3 | Warren F Smith | 16 | Son | — | Massachusetts |
| 4 | Arthur T Smith | 15 | Son | — | Massachusetts |
| 5 | William C Smith | 12 | Son | — | Massachusetts |
| 6 | Edith E Smith | 10 | Daughter | — | Massachusetts |
| 7 | Helen E Smith | 6 | Daughter | — | Massachusetts |
| 8 | Charles M Collins | 36 | Head | Mail Carrier | Massachusetts |
| 9 | Alice M Collins | 40 | Wife | — | Massachusetts |
| 10 | Frances R Collins | 8 | Daughter | — | Massachusetts |
| 11 | Alice Marie Collins | 3 | Daughter | — | Massachusetts |
| 12 | William J Martin | 45 | Head | — | Massachusetts |
| 13 | Mary L Martin | 43 | Wife | — | Massachusetts |
| 14 | Helen K Martin | 19 | Daughter | — | Massachusetts |
| 15 | Marie P Martin | 17 | Daughter | — | Massachusetts |
| 16 | Rita L Martin | 14 | Daughter | — | Massachusetts |
| 17 | William J Martin | 11 | Son | — | Massachusetts |
| 18 | Francis T Martin | 9 | Son | — | Massachusetts |
| 19 | — | None | — | — | — |
| 20 | Charlotte Stedman | 55 | Head | — | Massachusetts |
| 21 | Marion G Stedman | 36 | Daughter | Stenographer | Massachusetts |
| 22 | Arthur R Stedman | 33 | Son | E. Button Press | Massachusetts |
| 23 | Dwight H Davis | 31 | Head | Insurancy | New Hampshire |
| 24 | Elizabeth P Davis | 30 | Wife | Teacher | Massachusetts |
| 25 | Dwight Alan Davis | 4 | Son | — | Massachusetts |
| 26 | Andrew Garrity | 65 | Head | Teamster | Eire |
| 27 | Helen Garrity | 58 | Wife | — | Eire |
| 28 | Thomas P Garrity | 29 | Son | Lithographer | Massachusetts |
| 29 | Andrew J Garrity | 21 | Son | Clerk | Massachusetts |
| 30 | Patrick J Griffin | 57 | Head | Teamster | Eire |
| 31 | Ellen T Griffin | 58 | Wife | — | Eire |
| 32 | Gerald A Griffin | 25 | Son | Salesman | Massachusetts |
| 33 | Mary E Griffin THIS PERSON | 21 | Daughter | Filing Clerk | Massachusetts |
| 34 | Patrick J Jr Griffin | 15 | Son | Clerk | Massachusetts |
| 35 | Ethel Mcdonough | 55 | Head | — | York |
| 36 | David L Mcdonough | 24 | Son | Machinist | Massachusetts |
| 37 | Ruth Mcdonough | 19 | Daughter | Private Secretary | Massachusetts |
| 38 | Robert Mcdonough | 16 | Son | — | Massachusetts |
| 39 | Elsie M Mcdonough | 14 | Daughter | — | Massachusetts |
| 40 | George W Wilson | 56 | Head | Car Packer | Massachusetts |
Pedigree Summary
Mary + 2 siblings
Gen 1 · 4 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)