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Mary Kirby — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Winnebago-County, Illinois
Our Model Tree links this Mary Kirby across the 1920, 1930 and 1940 US Censuses in Winnebago-County, Illinois (XGBoost, ~Confirmed) — first a head (b.~1860), then head of a 2-person household.
Age 80
b. ~1860
Female
Head
Born: Illinois
Widowed
1940 Census Record Details
| Census Year | 1940 |
| Location | Winnebago-County, Illinois |
| Surname | Kirby |
| Given Name | Mary L |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 80 |
| Marital Status | Widowed |
| Birthplace | Illinois |
| 1935 Residence (City) | Rockford |
| 1935 Residence (County) | Winnebago |
| Additional Details | |
| Highest Grade | 6 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Rockford |
| Est. Birth Year | ~1860 |
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.
2 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| William Kirby | Son | — | 39 | ~1901 |
| Mary Kirby | Head | — | 80 | ~1860 |
Census Appearances
1920
Winnebago, Illinois
Spouse, age 55
Winnebago, Illinois · implied b. ~1865 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kirby |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 55 |
| Marital Status | Married |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Winnebago, Illinois
Other, age 69
Winnebago, Illinois · implied b. ~1861 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kirby |
| Given Name | Mary |
| Relationship to Head | Wife-H |
| Sex | F |
| Color / Race | White |
| Age | 69 |
| Marital Status | Married |
| Birthplace | Illinois |
| Age at First Marriage | 15 |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Winnebago-County, Illinois
Head, age 80
Winnebago-County, Illinois · implied b. ~1860 — 2 household members
| Surname | Kirby |
| Given Name | Mary L |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 80 |
| Marital Status | Widowed |
| Birthplace | Illinois |
| 1935 Residence (City) | Rockford |
| 1935 Residence (County) | Winnebago |
| Highest Grade | 6 |
| 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 Kirby across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Kirby
Head · 1940 · age 80 · b. ~1860 · Illinois
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Winnebago-County, Illinois
Open full size
1940 US Federal Census — Winnebago-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00915-00435)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Peter J Leneen | 15 | Son | — | Illinois |
| 2 | Neil J Leneen | 11 | Son | — | Illinois |
| 3 | Otto De King | 48 | Lodger | — | Illinois |
| 4 | Raymond Keating | 46 | Head | Watchman | Wisconsin |
| 5 | Helma E Keating | 42 | Wife | — | Minnesota |
| 6 | Margaret F Keating | 16 | Daughter | — | Minnesota |
| 7 | Richard W Keating | 15 | Daughter | — | Iowa |
| 8 | Robert H Keating | 13 | Son | — | Iowa |
| 9 | Delores M Keating | 10 | Daughter | — | Iowa |
| 10 | Raymond Keating | 7 | Son | — | Illinois |
| 11 | Janet M Keating | 4 | Daughter | — | Illinois |
| 12 | Willard Wilt | 48 | Head | Assembler | Illinois |
| 13 | Dorcas Wilt | 46 | Wife | — | Wisconsin |
| 14 | Willard P Wilt | 12 | Son | — | Illinois |
| 15 | William Boulton | 45 | Head | Business Agent | Illinois |
| 16 | Georgia Boulton | 34 | Wife | Small Assembler | Iowa |
| 17 | Nicholas J Smith | 53 | Head | Truck Driver | Iowa |
| 18 | Martha A Smith | 43 | Wife | — | Iowa |
| 19 | Helen Mae Smith | 16 | Daughter | — | Iowa |
| 20 | Verlen Bill Smith | 13 | Son | — | Iowa |
| 21 | Evelen K Smith | 10 | Daughter | — | Illinois |
| 22 | Cynthia Smith | 5 | Daughter | — | Illinois |
| 23 | Ernest Smith | 1 | Son | — | Illinois |
| 24 | Thomas Reed | 70 | Head | — | Iowa |
| 25 | Mary L Kirby THIS PERSON | 80 | Head | — | Illinois |
| 26 | William F Kirby | 39 | Son | — | Illinois |
| 27 | Everett J Rainer | 38 | Head | Belt Sander | Illinois |
| 28 | Lola L Rainer | 41 | Wife | — | Illinois |
| 29 | Charles E Rainer | 4 | Son | — | Illinois |
| 30 | Charles W Wood | 55 | Head | Painter & Decorator | Illinois |
| 31 | Cora A Wood | 54 | Wife | — | Illinois |
| 32 | Curtis M Wood | 16 | Son | New Worker | Illinois |
| 33 | Ben Dunauski | 47 | Head | Heat Treating | Lithuania |
| 34 | Alice V Dunauski | 38 | Wife | — | Lithuania |
| 35 | Alice A Dunauski | 2 | Daughter | — | Illinois |
| 36 | Benita J Dunauski | 0 | Daughter | — | Illinois |
| 37 | Frank King | 52 | Head | Labourer | Illinois |
| 38 | Florence M King | 51 | Wife | — | Wisconsin |
| 39 | Herman Stewart | 29 | Step Son | Labourer | Illinois |
| 40 | John L Stewart | 22 | Step Son | — | 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)