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Mary Lyons — 1940 US Census Record
Model Tree available1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this Mary Lyons across the 1920, 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed), with identified parents William & Delia — first a daughter (b.~1910), then head of a 3-person household.
Age 30
b. ~1910
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | LYONS |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | SUFFOLK |
| Additional Details | |
| Occupation | Bookkeeper |
| Industry | Artificial Dress Maker |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1345 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Bookkeeper |
| Township / Ward | Boston City |
| 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.
3 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Lyons | Daughter | — | 30 | ~1910 |
| Delia Lyons | Head | — | 64 | ~1876 |
| Thomas Lyons | Son | — | 36 | ~1904 |
Census Appearances
1920
Suffolk, Massachusetts
Daughter, age 10
Suffolk, Massachusetts · implied b. ~1910 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lyons |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Suffolk, Massachusetts
Daughter, age 21
Suffolk, Massachusetts · implied b. ~1909 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lyons |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Clerk |
| Industry | Dress shop |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Daughter, age 30
Suffolk-County, Massachusetts · implied b. ~1910 — 3 household members
| Surname | LYONS |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | SUFFOLK |
| Occupation | Bookkeeper |
| Industry | Artificial Dress Maker |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1345 |
| 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 Mary Lyons across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father William Lonergan (~0.92 confidence) and mother Delia Lyons (~0.92 confidence) and mother Mary Lonergan (~0.92 confidence) and mother Delia Lyons (~0.92 confidence). The pedigree spans 1 generation with 4 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
William Lonergan
b. ~1868
Source father
● Household
· direct · ~0.92
Mother
Delia Lyons
b. ~1874
Source mother
● Household
· direct · ~0.92
Mother
Mary Lonergan
b. ~1876
Source mother
● Household
· direct · ~0.92
Mother
Delia Lyons
b. ~1876
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Lyons
Daughter · 1940 · age 30 · b. ~1910 · Massachusetts
★ You are viewing this record
Sibling
Thomas Lyons
Sibling · 1940 · age 36
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-t0627-01682-00389)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Catherine Gibbons | 16 | Daughter | — | Massachusetts |
| 42 | Joseph Keefe | 26 | Head | Claim Adjuster | Massachusetts |
| 43 | Thomas Keefe | 25 | Stepson | Bartender | Massachusetts |
| 44 | Francis Keefe | 23 | Stepson | Shoe Repair | Massachusetts |
| 45 | Patrick J. Lee | 56 | Head | Street Car Operator | Irish Free State |
| 46 | Mary E. Lee | 50 | Wife | — | Irish Free State |
| 47 | Mary Tensel | 18 | Niece | — | Massachusetts |
| 48 | Mary Tuohy | 51 | Head | — | Irish Free State |
| 49 | Thomas Tuohy | 22 | Son | Station Attendant | Massachusetts |
| 50 | Marguerite Tuohy | 21 | Daughter | Beautician | Massachusetts |
| 51 | William D. Farrell | 55 | Head | Plumber | Massachusetts |
| 52 | Annie Farrell | 54 | Wife | — | Irish Free State |
| 53 | Catherine Farrell | 28 | Daughter | Sales Girl | Massachusetts |
| 54 | Anna Farrell | 16 | Daughter | — | Massachusetts |
| 55 | Delia Lyons | 64 | Head | — | Irish Free State |
| 56 | Thomas J. Lyons | 36 | Son | Credit Filing Clerk | Massachusetts |
| 57 | Mary Lyons THIS PERSON | 30 | Daughter | Bookkeeper | Massachusetts |
| 58 | Margaret Handrahan | 65 | Head | — | Northern Ireland |
| 59 | Mary Handrahan | 28 | Daughter | Bookkeeper | Massachusetts |
| 60 | Carolyn Handrahan | 24 | Daughter | Cost Clerk | Massachusetts |
| 61 | Extra Line Handrahan | None | — | — | — |
| 62 | John J. Ryan | 62 | Head | Carpenter | Irish Free State |
| 63 | Roseann Ryan | 63 | Wife | — | Massachusetts |
| 64 | Helen Ryan | 31 | Daughter | Hygienist | Massachusetts |
| 65 | Thomas Carter | 57 | Head | Messenger | Massachusetts |
| 66 | Mary A. Carter | 56 | Wife | — | Massachusetts |
| 67 | John J. Wall | 39 | Head | Blacksmith | Massachusetts |
| 68 | Florence T. Wall | 38 | Wife | — | Massachusetts |
| 69 | John A. Wall | 14 | Son | — | Massachusetts |
| 70 | Anne M. Wall | 8 | Daughter | — | Massachusetts |
| 71 | Claire M. Wall | 6 | Daughter | — | Massachusetts |
| 72 | Diane Wall | 1 | Daughter | — | Massachusetts |
| 73 | Nora Sullivan | 78 | Head | — | Irish Free State |
| 74 | Patrick Largey | 45 | Head | Floor Man | Northern Ireland |
| 75 | Paul V. Largey | 22 | Son | Butcher | Massachusetts |
| 76 | Anna M. Largey | 19 | Daughter | File Clerk | Massachusetts |
| 77 | Helen P. Largey | 17 | Daughter | — | Massachusetts |
| 78 | Margaret M. Largey | 15 | Daughter | — | Massachusetts |
| 79 | Donald F. Largey | 13 | Son | — | Massachusetts |
| 80 | Edward Largey | 11 | Son | — | Massachusetts |
Pedigree Summary
Mary + 1 sibling
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)