JC
James Costello — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this James Costello across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1929), then head of a 8-person household.
Age 11
b. ~1929
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Costello |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago city |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1929 |
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.
8 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to James | Age | Birth yr |
|---|---|---|---|---|
| Mary Costello | Spouse | — | 47 | ~1893 |
| Susanna Costello | Daughter | — | 8 | ~1932 |
| David Costello | Son | — | 5 | ~1935 |
| Rosemary Costello | Daughter | — | 17 | ~1923 |
| Joseph Costello | Son | — | 15 | ~1925 |
| Patrick Costello | Head | — | 53 | ~1887 |
| James Costello | Son | — | 11 | ~1929 |
| Patricia Costello | Daughter | — | 14 | ~1926 |
Census Appearances
1930
Cook, Illinois
Son, age 1
Cook, Illinois · implied b. ~1929 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Costello |
| Given Name | James |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | England |
| Mother's Birthplace | Wisconsin |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 11
Cook-County, Illinois · implied b. ~1929 — 8 household members
| Surname | Costello |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago city |
| 1935 Residence (County) | Cook |
| Highest Grade | No 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 James Costello across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
James Costello
Son · 1940 · age 11 · b. ~1929 · Illinois
★ You are viewing this record
Sibling
Joseph Costello
Sibling · 1940 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Patricia Costello
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Rosemary Costello
Sibling · 1940 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Susanna Costello
Sibling · 1940 · age 8
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
David Costello
Sibling · 1940 · age 5
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
36 people indexed on this census page (nara:1940:m-t0627-00948-01055)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Lena Henke | 44 | Head | — | Illinois |
| 2 | Marguerite Mcaley | 30 | Daughter | Order Clerk | Illinois |
| 3 | Ruth Hugh | 25 | Daughter | Assembler | Illinois |
| 4 | Joseph Mcaley | 6 | Grandson | — | Illinois |
| 5 | Raymond Hugh | 5 | Grandson | — | Illinois |
| 7 | Marvin Fishbeck | 20 | Head | Assembler | Texas |
| 8 | Christine Fishbeck | 17 | Wife | — | Illinois |
| 9 | Phyllis Fishbeck | 1 | Daughter | — | Illinois |
| 10 | Fred Fishbeck | 45 | Head | Carpenter | Michigan |
| 11 | Inzy Fishbeck | 42 | Wife | — | Illinois |
| 12 | Richard Fishbeck | 18 | Son | — | Illinois |
| 13 | James Fishbeck | 15 | Son | — | Texas |
| 14 | Norman Fishbeck | 7 | Son | — | Illinois |
| 16 | Patrick Costello | 53 | Head | Car Inspector | England |
| 17 | Mary Costello | 47 | Wife | — | Ireland |
| 18 | Rosemary Costello | 17 | Daughter | — | Illinois |
| 19 | Joseph Costello | 15 | Son | — | Illinois |
| 20 | Patricia Costello | 14 | Daughter | — | Illinois |
| 21 | James Costello THIS PERSON | 11 | Son | — | Illinois |
| 22 | Susanna Costello | 8 | Daughter | — | Illinois |
| 23 | David Costello | 5 | Son | — | Illinois |
| 24 | Ross Eldorado | 51 | Head | Stationary Engineer | Italy |
| 25 | Marie Eldorado | 38 | Wife | — | Italy |
| 26 | Louis Eldorado | 19 | Son | — | Illinois |
| 27 | James Eldorado | 14 | Son | — | Illinois |
| 28 | Richard Eldorado | 11 | Son | — | Illinois |
| 30 | Walter Gryzello | 53 | Head | Parts Inspector | Poland |
| 31 | Maria Gryzello | 44 | Wife | — | Poland |
| 33 | Albert Noble | 55 | Head | Laborer | Illinois |
| 34 | Anna Noble | 48 | Wife | — | Illinois |
| 35 | Henry Krichel | 27 | Lodger | Laborer | Minnesota |
| 36 | Arthur Demit | 54 | Head | Miller | Iowa |
| 37 | Lela Demit | 49 | Wife | — | Iowa |
| 38 | Harold Demit | 25 | Son | Maintenance Man | Iowa |
| 39 | Gladys Demit | 5 | Daughter | — | Illinois |
| 40 | Pauline Sullivan | 61 | Head | Seamstress | Germany |
Related Census Records
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)