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Mary Lester — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Lester across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a daughter (b.~1921), then head of a 7-person household.
Age 19
b. ~1921
Female
Daughter
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Lester |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | Hs 4 |
| 1935 Residence | Same Place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1921 |
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 |
|---|---|---|---|---|
| Eleanor Lester | Daughter | — | 13 | ~1927 |
| Nick Lester | Head | — | 47 | ~1893 |
| Doris Lester | Daughter | — | 27 | ~1913 |
| Antoinette Lester | Spouse | — | 46 | ~1894 |
| Roger Lester | Son | — | 1 | ~1939 |
| Beatrice Lester | Daughter | — | 14 | ~1926 |
| Mary Lester | Daughter | — | 19 | ~1921 |
Census Appearances
1930
Cook, Illinois
Daughter, age 9
Cook, Illinois · implied b. ~1921 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lestoral |
| Given Name | Marjorie |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 9 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Jugoslavia |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Daughter, age 19
Cook-County, Illinois · implied b. ~1921 — 7 household members
| Surname | Lester |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Highest Grade | Hs 4 |
| 1935 Residence | Same Place |
| 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 Mary Lester across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Lester
Daughter · 1940 · age 19 · b. ~1921 · Illinois
★ You are viewing this record
Sibling
Eleanor Lester
Sibling · 1940 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Doris Lester
Sibling · 1940 · age 27
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Roger Lester
Sibling · 1940 · age 1
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Beatrice Lester
Sibling · 1940 · age 14
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
40 people indexed on this census page (nara:1940:m-t0627-00952-00282)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Marie Ellen Timmerman | 12 | daughter | — | Illinois |
| 2 | Gladys Timmerman | 10 | daughter | — | Illinois |
| 3 | Earl Timmerman | 6 | son | — | Illinois |
| 4 | Allan Courtney | 49 | head | Paving Engineer | Indiana |
| 5 | Helen Courtney | 54 | wife | — | Illinois |
| 6 | Edward Lee Kain | 50 | head | Mechanic | Ohio |
| 7 | Anna E. Kain | 52 | wife | — | Illinois |
| 8 | Joseph P. Fisher | 54 | head | Switchboard Repairman | Michigan |
| 9 | Irene Fisher | 35 | wife | Assistant Accountant | England |
| 10 | Marlene Fisher | 11 | daughter | — | Illinois |
| 11 | Cornelius Mccarthey | 42 | head | Fireman | Illinois |
| 12 | Nona Mccarthey | 43 | wife | — | Illinois |
| 13 | Eugene Mccarthey | 24 | son | Cutting Machine Operator | Illinois |
| 14 | Nick Lester | 47 | head | Laborer | Yugoslavia |
| 15 | Antoinette Lester | 46 | wife | — | Yugoslavia |
| 16 | Doris Lester | 27 | daughter | Salesgirl | Yugoslavia |
| 17 | Mary Lester THIS PERSON | 19 | daughter | — | Illinois |
| 18 | Beatrice Lester | 14 | daughter | — | Illinois |
| 19 | Eleanor Lester | 13 | daughter | — | Illinois |
| 20 | Roger Lester | 1 | son | — | Illinois |
| 21 | Charles Vercouter | 43 | head | Fireman | Illinois |
| 22 | Nell Vercouter | 42 | wife | — | Illinois |
| 23 | Charles F. Vercouter | 22 | son | Assembler | Illinois |
| 24 | Jean Vercouter | 15 | daughter | — | Illinois |
| 25 | Jack C. Borrelli | 39 | head | Insurance Agent | Georgia |
| 26 | Agnes Borrelli | 42 | wife | — | Illinois |
| 27 | Don Borrelli | 4 | son | — | Illinois |
| 28 | Leonard Olson | 45 | head | Lineman | Wisconsin |
| 29 | Rose Olson | 38 | wife | — | Illinois |
| 30 | Rose Kleefeld | 76 | mother | — | Ohio |
| 31 | Clarence Kleefeld | 33 | brother-in-law | Accountant | Illinois |
| 32 | William Cyzner | 55 | head | Butcher | Lithuania |
| 33 | Stella Cyzner | 50 | wife | — | Lithuania |
| 34 | Sophie Cyzner | 24 | daughter | Laborer | Illinois |
| 35 | Ellen Cyzner | 18 | daughter | Receptionist | Illinois |
| 36 | Gregory V. Galuby | 37 | head | Painter | Russia |
| 37 | Pauline Galuby | 27 | wife | — | Illinois |
| 38 | David R. Galuby | 2 | son | — | Illinois |
| 39 | Joseph Lasker | 52 | head | Sheet Metal Worker | Hungary |
| 40 | Anna Lasker | 47 | wife | — | Hungary |
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)