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Lillian Peterson — 1940 US Census Record
Model Tree available1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Lillian Peterson across the 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed), with identified parents Peter & Peter — first a daughter (b.~1899), then head of a 4-person household.
Age 41
b. ~1899
Female
Daughter
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Peterson |
| Given Name | Lillian |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 41 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | school teacher |
| Industry | public school |
| Class of Worker | PW |
| Hours Worked | 35 |
| Income (1939) | 2300 |
| Highest Grade | C 4 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Teacher |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1899 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Lillian | Age | Birth yr |
|---|---|---|---|---|
| Bertha Peterson | Daughter | — | 47 | ~1893 |
| Lillian Peterson | Daughter | — | 41 | ~1899 |
| Peter Peterson | Head | — | 85 | ~1855 |
| Amanda Peterson | Spouse | — | 76 | ~1864 |
Census Appearances
1920
Cook, Illinois
Daughter, age 20
Cook, Illinois · implied b. ~1900 — 10 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Peterson |
| Given Name | Lillian |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Sweden |
| Mother's Birthplace | Sweden |
| Occupation | Stenographer |
| Industry | Telephone Co |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Cook, Illinois
Daughter, age 30
Cook, Illinois · implied b. ~1900 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Peterson |
| Given Name | Lillian A |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Sweden |
| Mother's Birthplace | Sweden |
| Occupation | Teacher |
| Industry | Public School |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Daughter, age 41
Cook-County, Illinois · implied b. ~1899 — 4 household members
| Surname | Peterson |
| Given Name | Lillian |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 41 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Occupation | school teacher |
| Industry | public school |
| Class of Worker | PW |
| Hours Worked | 35 |
| Income (1939) | 2300 |
| Highest Grade | C 4 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
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 Lillian Peterson across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Peter Peterson (~0.92 confidence) and father Peter Peterson (~0.92 confidence) and mother Amanda Peterson (~0.92 confidence) and mother Ellen Peterson (~0.92 confidence) and mother Katy Foss (~0.92 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Peter Peterson
b. ~1855
Source father
● Household
· direct · ~0.92
Father
Peter Peterson
b. ~1855
Source father
● Household
· direct · ~0.92
Mother
Amanda Peterson
b. ~1864
Source mother
● Household
· direct · ~0.92
Mother
Ellen Peterson
b. ~1873
Source mother
● Household
· direct · ~0.92
Mother
Katy Foss
b. ~1876
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Lillian Peterson
Daughter · 1940 · age 41 · b. ~1899 · Illinois
★ You are viewing this record
Sibling
Bertha Peterson
Sibling · 1940 · age 47
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 — Cook-County, Illinois
Open full size
1940 US Federal Census — Cook-County, Illinois
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-00935-00270)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Nadine Randall | 35 | wife | — | Indiana |
| 42 | William Mcedward | 71 | head | Buyer | Canada |
| 43 | Wilbur B Mcedward | 30 | son | Sales Promoter | Illinois |
| 44 | Henrietta Mcedward | 30 | daughter in law | — | Illinois |
| 45 | Carol Mcedward | 1 | grandchild | — | Illinois |
| 46 | Dorothy Daley | 30 | maid | Maid | Illinois |
| 47 | Gustave Peterson | 54 | head | Cashier | Illinois |
| 48 | Agnes Peterson | 48 | wife | — | Missouri |
| 49 | Florence Arnold | 73 | boarder | — | New York |
| 50 | Peter B Peterson | 85 | head | — | Sweden |
| 51 | Amanda Peterson | 76 | wife | — | Sweden |
| 52 | Bertha Peterson | 47 | daughter | Clerk | Illinois |
| 53 | Lillian Peterson THIS PERSON | 41 | daughter | School Teacher | Illinois |
| 55 | Wilbert Cummings | 34 | head | Field Engineer | Missouri |
| 56 | Mildred Cummings | 30 | wife | — | Indiana |
| 57 | Joan Cummings | 5 | daughter | — | Indiana |
| 58 | Marshall Smith | 28 | head | Cashier | Illinois |
| 59 | Florence Smith | 26 | wife | — | Illinois |
| 60 | Marjorie Smith | 2 | daughter | — | Illinois |
| 61 | Robert Pebworth | 31 | head | Journalist | Indiana |
| 62 | Mary Pebworth | 28 | wife | — | Indiana |
| 63 | Robert C Jr Pebworth | 0 | son | — | Indiana |
| 64 | Martha Mull | 23 | law | — | Indiana |
| 65 | Hugh Curtiss | 47 | head | Traffic Manager | Connecticut |
| 66 | Ella Curtiss | 51 | wife | — | New York |
| 67 | Leland E Reaney | 37 | head | C.P.A. | Illinois |
| 68 | Rose Reaney | 36 | wife | — | Michigan |
| 69 | Paul Edward Reaney | 4 | son | — | Illinois |
| 70 | Leland E Jr Reaney | 2 | son | — | Illinois |
| 71 | Violet Cargill | 45 | head | Secretary | Wisconsin |
| 72 | Hazel Cargill | 20 | daughter | — | Illinois |
| 73 | Anna Frank | 75 | mother | — | Wisconsin |
| 74 | Arden Freel | 32 | head | Civil Engineer | Iowa |
| 75 | Gladys Freel | 31 | wife | — | Iowa |
| 76 | Delmar Beaumont | 35 | head | Treasurer | Illinois |
| 77 | Miriam Beaumont | 34 | wife | — | Illinois |
| 78 | Carol Beaumont | 11 | daughter | — | Illinois |
| 79 | Charles Moore | 67 | head | Draftsman | Canada |
| 80 | Ethyl Moore | 65 | wife | Practitioner | Missouri |
Pedigree Summary
Lillian + 1 sibling
Gen 1 · 5 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)