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Mary Lamb — 1940 US Census Record
Model Tree available1940 United States Federal Census · Allegheny-County, Pennsylvania
Our Model Tree links this Mary Lamb across the 1920, 1930 and 1940 US Censuses in Allegheny-County, Pennsylvania (XGBoost, ~Confirmed), with identified parents William & Anna — first a daughter (b.~1913), then head of a 5-person household.
Age 27
b. ~1913
Female
Daughter
Born: Pennsylvania
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Allegheny-County, Pennsylvania |
| Surname | Lamb |
| Given Name | Mary C. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 27 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Additional Details | |
| Occupation | Teacher |
| Industry | Public School |
| Class of Worker | PW |
| Hours Worked | 44 |
| Income (1939) | 1800 |
| Highest Grade | C 4 |
| 1935 Residence | Same Place |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
| Occupation | Teacher |
| Township / Ward | Pittsburgh |
| Est. Birth Year | ~1913 |
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 Lamb | Daughter | — | 27 | ~1913 |
| Thomas Lamb | Son | — | 20 | ~1920 |
| Alice Lamb | Daughter | — | 23 | ~1917 |
| Mary Lamb | Spouse | — | 60 | ~1880 |
| William Lamb | Head | — | 61 | ~1879 |
Census Appearances
1920
Allegheny, Pennsylvania
Daughter, age 6
Allegheny, Pennsylvania · implied b. ~1914 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lamb |
| Given Name | Margaret |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 6 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | England |
| Occupation | none |
| Speaks English | Yes |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1930
Allegheny, Pennsylvania
Daughter, age 16
Allegheny, Pennsylvania · implied b. ~1914 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lamb |
| Given Name | Margaret |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| Father's Birthplace | Pennsylvania |
| Mother's Birthplace | England |
| Can Read/Write | Yes |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
1940
Allegheny-County, Pennsylvania
Daughter, age 27
Allegheny-County, Pennsylvania · implied b. ~1913 — 5 household members
| Surname | Lamb |
| Given Name | Mary C. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 27 |
| Marital Status | Single |
| Birthplace | Pennsylvania |
| 1935 Residence (City) | Pittsburgh |
| 1935 Residence (County) | Allegheny |
| Occupation | Teacher |
| Industry | Public School |
| Class of Worker | PW |
| Hours Worked | 44 |
| Income (1939) | 1800 |
| Highest Grade | C 4 |
| 1935 Residence | Same Place |
| Birth State | Pennsylvania |
| Birth Country | United States |
| Birthplace (normalized) | pennsylvania |
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 Lamb across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father William Lamb (~0.92 confidence) and mother Anna Lamb (~0.92 confidence) and mother Mary Lamb (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
William Lamb
b. ~1879
Source father
● Household
· direct · ~0.92
Mother
Anna Lamb
b. ~1880
Source mother
● Household
· direct · ~0.92
Mother
Mary Lamb
b. ~1880
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Lamb
Daughter · 1940 · age 27 · b. ~1913 · Pennsylvania
★ You are viewing this record
Sibling
Thomas Lamb
Sibling · 1940 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Alice Lamb
Sibling · 1940 · age 23
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 — Allegheny-County, Pennsylvania
Open full size
1940 US Federal Census — Allegheny-County, Pennsylvania
Page Contents
37 people indexed on this census page (nara:1940:m-t0627-03670-00462)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | William J. Lamb | 61 | Head | Order Clerk | Pennsylvania |
| 42 | Mary C. Lamb | 60 | Wife | — | Pennsylvania |
| 43 | Mary C. Lamb THIS PERSON | 27 | Daughter | Teacher | Pennsylvania |
| 44 | Alice Lamb | 23 | Daughter | Dietician | Pennsylvania |
| 45 | Thomas Lamb | 20 | Son | — | Pennsylvania |
| 46 | Mary Hartz | 65 | Head | Teacher | Pennsylvania |
| 47 | Ralph Albertine Hartz | 54 | Sister | — | Pennsylvania |
| 48 | Peter Walker | 69 | Head | Punching Clerk | Pennsylvania |
| 49 | Cora L. Walker | 69 | Wife | — | Ohio |
| 50 | Ralph Walker | 35 | Head | Railway Mail Clerk | Pennsylvania |
| 51 | Bertha Walker | 38 | Wife | — | Pennsylvania |
| 52 | Arthur M. Walker | 9 | Son | — | New York |
| 53 | Elizabeth Walker | 4 | Daughter | — | New York |
| 54 | Raymond Walker | 3 | Son | — | Pennsylvania |
| 55 | Francis Whalen | 32 | Head | Draftsman | Pennsylvania |
| 56 | Mary A. Whalen | 32 | Wife | — | Pennsylvania |
| 57 | Eleanor C. Whalen | 61 | Mother | — | Pennsylvania |
| 58 | Kathleen Whalen | 9 | Daughter | — | Pennsylvania |
| 59 | Mary Ellen Whalen | 4 | Daughter | — | Pennsylvania |
| 60 | Jane Frances Whalen | 2 | Daughter | — | Pennsylvania |
| 61 | E. E. Leroy | 56 | Head | Clergyman | Kansas |
| 62 | Olie B. Leroy | 52 | Wife | — | Pennsylvania |
| 63 | Harold Leroy | 30 | Son | Teacher | Pennsylvania |
| 64 | Doris M. Leroy | 27 | Daughter-in-law | — | Pennsylvania |
| 65 | Donna Lavonne Leroy | 2 | Granddaughter | — | Pennsylvania |
| 66 | Nellie Meyer | 65 | Head | — | Pennsylvania |
| 67 | Charlotte Meyer | 41 | Daughter | Sewing | Pennsylvania |
| 68 | R. J. Wunnenkuich | 44 | Head | Machinist | Pennsylvania |
| 69 | Catherine Wunnenkuich | 48 | Sister | Waitress | Pennsylvania |
| 70 | Minnie Wunnenkuich | 50 | Sister | — | Pennsylvania |
| 71 | William Oberle | 72 | Head | Bookkeeper | Pennsylvania |
| 72 | Mary Oberle | 61 | Wife | — | Germany |
| 73 | Gerard Oberle | 30 | Son | Jeweler | Pennsylvania |
| 74 | Gertrude Oberle | 28 | Daughter | — | Pennsylvania |
| 75 | William Oberle | 25 | Son | Roofer | Pennsylvania |
| 76 | Leonard Oberle | 21 | Son | Pattern Maker | Pennsylvania |
| 77 | Francis Oberle | 17 | Son | — | Pennsylvania |
Pedigree Summary
Mary + 2 siblings
Gen 1 · 3 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)