JM
John Maher — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Grundy-County, Illinois
Our Model Tree links this John Maher across the 1930 and 1940 US Censuses in Grundy-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1923), then head of a 10-person household.
Age 17
b. ~1923
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Grundy-County, Illinois |
| Surname | Maher |
| Given Name | John D |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Garfield Twp |
| 1935 Residence (County) | 40 |
| Additional Details | |
| Occupation | PW |
| Industry | 450 |
| Highest Grade | H-4 |
| 1935 Residence | Laborer |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Pw |
| Township / Ward | Garfield Twp |
| Est. Birth Year | ~1923 |
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.
10 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Joseph Maher | Son | — | 3 | ~1937 |
| Mollie Maher | Daughter | — | 8 | ~1932 |
| Barbara Maher | Daughter | — | 6 | ~1934 |
| Arthur Maher | Son | — | 12 | ~1928 |
| Theresa Maher | Daughter | — | 10 | ~1930 |
| John Maher | Son | — | 17 | ~1923 |
| Frances Maher | Spouse | — | 48 | ~1892 |
| Francis Maher | Daughter | — | 14 | ~1926 |
| Thomas Maher | Son | — | 19 | ~1921 |
| Thomas Maher | Head | — | 50 | ~1890 |
Census Appearances
1930
Grundy, Illinois
Son, age 7
Grundy, Illinois · implied b. ~1923 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Maher |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 7 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Grundy-County, Illinois
Son, age 17
Grundy-County, Illinois · implied b. ~1923 — 10 household members
| Surname | Maher |
| Given Name | John D |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Garfield Twp |
| 1935 Residence (County) | 40 |
| Occupation | PW |
| Industry | 450 |
| Highest Grade | H-4 |
| 1935 Residence | Laborer |
| 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 Maher across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Maher
Son · 1940 · age 17 · b. ~1923 · Illinois
★ You are viewing this record
Sibling
Joseph Maher
Sibling · 1940 · age 3
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Theresa Maher
Sibling · 1940 · age 10
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Thomas Maher
Sibling · 1940 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Arthur Maher
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Barbara Maher
Sibling · 1940 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Francis Maher
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mollie Maher
Sibling · 1940 · age 8
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 — Grundy-County, Illinois
Open full size
1940 US Federal Census — Grundy-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00809-00164)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Marlene Anderson | 3 | daughter | — | Illinois |
| 42 | Anne Marie Male | 55 | Head | — | Illinois |
| 43 | Raymond Male | 31 | son | Oa | Illinois |
| 44 | Ira Male | 23 | son | Gw | Illinois |
| 45 | Bettie Male | 17 | daughter | — | Illinois |
| 46 | Charles Male | 14 | son | — | Illinois |
| 47 | Otto Giannechini | 57 | Head | Laborer | Italy |
| 48 | Loraine Giannechini | 27 | Wife | — | Illinois |
| 49 | Aldo Giannechini | 3 | son | — | Illinois |
| 50 | Albert Giannechini | 2 | son | — | Illinois |
| 51 | Helmer Mortvedt | 56 | Head | Oa | Norway |
| 52 | Inga Mortvedt | 57 | Wife | — | Norway |
| 53 | John Mortvedt | 22 | son | Pw | Illinois |
| 54 | Carl Hansen | 58 | Head | Pw | Denmark |
| 55 | Cena Hansen | 55 | Wife | — | Denmark |
| 56 | Ida Hansen | 12 | daughter | — | Illinois |
| 57 | Thomas F Maher | 50 | Head | Oa | Illinois |
| 58 | Frances B Maher | 48 | Wife | — | Illinois |
| 59 | Thomas J Maher | 19 | son | — | Illinois |
| 60 | John D Maher THIS PERSON | 17 | son | Pw | Illinois |
| 61 | Francis Ann Maher | 14 | daughter | — | Illinois |
| 62 | Arthur Maher | 12 | son | — | Illinois |
| 63 | Theresa Maher | 10 | daughter | — | Illinois |
| 64 | Mollie G Maher | 8 | daughter | — | Illinois |
| 65 | Barbara Maher | 6 | daughter | — | Illinois |
| 66 | Joseph B Maher | 3 | son | — | Illinois |
| 67 | Bartholomew P Maher | 44 | Head | — | Illinois |
| 68 | Katherine Maher | 52 | Wife | — | Illinois |
| 69 | Alvin Hansen | 26 | Head | Oa | Illinois |
| 70 | Catherine Hansen | 21 | Wife | — | Illinois |
| 71 | Raymond Hansen | 19 | Head | Operator | Illinois |
| 72 | George Brooke | 44 | Head | Oa | Illinois |
| 73 | Pearl Brooke | 45 | Wife | — | Illinois |
| 74 | Dorothy Brooke | 19 | daughter | — | Illinois |
| 75 | Georgia B Brooke | 11 | daughter | — | Illinois |
| 76 | Frank Kratochvil | 46 | Head | Oa | Illinois |
| 77 | Ella Kratochvil | 42 | Wife | — | Illinois |
| 78 | Louise Kratochvil | 21 | daughter | Pw | Illinois |
| 79 | Dorothy Kratochvil | 18 | daughter | Pw | Illinois |
| 80 | Robert Kratochvil | 15 | son | Pw | Illinois |
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)