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John Sims — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this John Sims across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1926), then head of a 7-person household.
Age 14
b. ~1926
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Sims |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Cicero |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | S 8 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Cicero |
| Est. Birth Year | ~1926 |
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 John | Age | Birth yr |
|---|---|---|---|---|
| Catherine Sims | Spouse | — | 44 | ~1896 |
| George Sims | Son | — | 21 | ~1919 |
| Della Sims | Daughter | — | 20 | ~1920 |
| Arthur Sims | Son | — | 16 | ~1924 |
| George Sims | Head | — | 45 | ~1895 |
| John Sims | Son | — | 14 | ~1926 |
| Catherine Sims | Daughter | — | 19 | ~1921 |
Census Appearances
1930
Cook, Illinois
Son, age 4
Cook, Illinois · implied b. ~1926 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Sim |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Scotland |
| Mother's Birthplace | Scotland |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 14
Cook-County, Illinois · implied b. ~1926 — 7 household members
| Surname | Sims |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Cicero |
| 1935 Residence (County) | Cook |
| Highest Grade | S 8 |
| 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 John Sims across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Sims
Son · 1940 · age 14 · b. ~1926 · Illinois
★ You are viewing this record
Sibling
Della Sims
Sibling · 1940 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Arthur Sims
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
George Sims
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Catherine Sims
Sibling · 1940 · age 19
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-t0627-00777-00557)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Charles Kolar | 12 | Son | — | Illinois |
| 42 | Donald Kolar | 9 | Son | — | Illinois |
| 43 | Beverly Kolar | 2 | Daughter | — | Illinois |
| 44 | Frank Sr. Scott | 63 | Father | Foreman | Czechoslovakia |
| 45 | Gordon Scott | 43 | Head | Foreman | Vermont |
| 46 | Orlie Scott | 41 | Wife | — | Illinois |
| 47 | Orlie Scott | 19 | Daughter | Assembler | Illinois |
| 48 | Gordon Scott | 14 | Son | — | Illinois |
| 49 | Richard Scott | 13 | Son | — | Illinois |
| 50 | Charles Holoubek | 45 | Head | Laborer | Czechoslovakia |
| 51 | Rose Holoubek | 48 | Wife | — | Czechoslovakia |
| 52 | Rose Holoubek | 24 | Daughter | Typist | Illinois |
| 53 | John Holoubek | 20 | Son | Apprentice Machinist | Illinois |
| 54 | Ralph Stiglich | 54 | Head | Stationary Engineer | Yugoslavia |
| 55 | William Schneider | 23 | Son-in-law | Truck Driver | Illinois |
| 56 | Agnes Schneider | 19 | Daughter | — | Illinois |
| 57 | Virginia Schneider | 0 | Grand-daughter | — | Illinois |
| 58 | George Sims | 45 | Head | Tool Maker | Scotland |
| 59 | Catherine Sims | 44 | Wife | — | Scotland |
| 60 | George Sims | 21 | Son | Draftsman | Scotland |
| 61 | Della Sims | 20 | Daughter | Bookkeeper | Scotland |
| 62 | Catherine Sims | 19 | Daughter | Typist | Scotland |
| 63 | Arthur Sims | 16 | Son | Delivery | Illinois |
| 64 | John Sims THIS PERSON | 14 | Son | — | Illinois |
| 65 | John Plazyk | 43 | Head | Mailman | Illinois |
| 66 | Sophie Plazyk | 38 | Wife | — | Wisconsin |
| 67 | Floyd Plazyk | 13 | Son | — | Illinois |
| 68 | John Hermait | 32 | Head | Salesman | Illinois |
| 69 | Grace Hermait | 32 | Wife | — | Illinois |
| 70 | Peter Hermait | 4 | Son | — | Illinois |
| 71 | Joseph Malecek | 39 | Head | Service Man | Illinois |
| 72 | Marie Malecek | 38 | Wife | — | Wisconsin |
| 73 | Joseph Malecek | 14 | Son | — | Illinois |
| 74 | Richard Malecek | 10 | Son | — | Illinois |
| 75 | Marion Malecek | 7 | Daughter | — | Illinois |
| 76 | Anna May Malecek | 5 | Daughter | — | Illinois |
| 77 | Barbara Lee Malecek | 3 | Daughter | — | Illinois |
| 78 | Frank Horvat | 32 | Head | Electrical Repair | Illinois |
| 79 | Helen Horvat | 26 | Wife | — | Pennsylvania |
| 80 | Albert Knutson | 47 | Head | Milkman | Wisconsin |
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)