MK
Mary Kirby — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Sangamon-County, Illinois
Our Model Tree links this Mary Kirby across the 1920, 1930 and 1940 US Censuses in Sangamon-County, Illinois (XGBoost, ~Confirmed) — first a spouse (b.~1874), then head of a 4-person household.
Age 66
b. ~1874
Female
Spouse
Born: Missouri
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Sangamon-County, Illinois |
| Surname | Kirby |
| Given Name | Mary E. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 66 |
| Marital Status | Married |
| Birthplace | Missouri |
| 1935 Residence (City) | R |
| 1935 Residence (County) | Sangamon |
| Additional Details | |
| Highest Grade | No 8 |
| 1935 Residence | Illinois |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
| Township / Ward | Rochester Town |
| Est. Birth Year | ~1874 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Frank Kirby | Head | — | 70 | ~1870 |
| Mary Kirby | Spouse | — | 66 | ~1874 |
| Florence Evans | Daughter | — | 28 | ~1912 |
| Robert Evans | Other | — | 33 | ~1907 |
Census Appearances
1920
Sangamon, Illinois
Spouse, age 47
Sangamon, Illinois · implied b. ~1873 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kirby |
| Given Name | Mary C. |
| Relationship to Head | wife |
| Sex | F |
| Color / Race | White |
| Age | 47 |
| Marital Status | Married |
| Birthplace | Missouri |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
1930
Sangamon, Illinois
Spouse, age 56
Sangamon, Illinois · implied b. ~1874 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kirby |
| Given Name | Mary E. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 56 |
| Marital Status | Married |
| Birthplace | Missouri |
| Age at First Marriage | 22 |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
1940
Sangamon-County, Illinois
Spouse, age 66
Sangamon-County, Illinois · implied b. ~1874 — 4 household members
| Surname | Kirby |
| Given Name | Mary E. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 66 |
| Marital Status | Married |
| Birthplace | Missouri |
| 1935 Residence (City) | R |
| 1935 Residence (County) | Sangamon |
| Highest Grade | No 8 |
| 1935 Residence | Illinois |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
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
Spouse · 1940 · age 66 · b. ~1874 · 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 — Sangamon-County, Illinois
Open full size
1940 US Federal Census — Sangamon-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00887-00591)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Opal Kelly | 31 | Wife | — | Illinois |
| 42 | Morris Kelly | 5 | Son | — | — |
| 43 | George Fisher | 33 | Head | Engineer | Illinois |
| 44 | Dorothy B. Fisher | 31 | Wife | — | Illinois |
| 45 | Gilmore Earley | 38 | Head | Lineman | Kentucky |
| 46 | Lucille O. Earley | 32 | Wife | — | Illinois |
| 47 | Allan Earley | 0 | Son | — | Illinois |
| 48 | Emma L. Forsythe | 72 | Head | — | Illinois |
| 49 | Kenneth Campbell | 20 | Lodger | Laborer | Illinois |
| 50 | Laura Campbell | 17 | Lodger | — | Illinois |
| 51 | Dr. F. D. Wright | 58 | Head | Medical | Illinois |
| 52 | Ruth Wright | 58 | Wife | — | Illinois |
| 53 | Elizabeth Wright | 21 | Daughter | — | Illinois |
| 54 | Frank Kirby | 70 | Head | — | Illinois |
| 55 | Mary E. Kirby THIS PERSON | 66 | Wife | — | Missouri |
| 56 | Robert H. Evans | 33 | Son-in-law | Laborer | Illinois |
| 57 | Florence E. Evans | 28 | Daughter | — | Illinois |
| 58 | Dora Roe | 69 | Head | — | Illinois |
| 59 | Thompson Harris | 93 | Head | — | Kentucky |
| 60 | Elizabeth Yeaman | 52 | Niece | — | Illinois |
| 61 | Robert Dickerson | 22 | Head | Attendant | Illinois |
| 62 | Evelyn Dickerson | 21 | Wife | — | Illinois |
| 63 | Kenneth Dickerson | 29 | Brother | Truck Driver | Illinois |
| 64 | Herschel Richardson | 28 | Head | Manager | Illinois |
| 65 | Beulah Richardson | 22 | Wife | — | Illinois |
| 66 | F. B. Harcourt | 84 | Head | — | Indiana |
| 67 | Minnie C. Harcourt | 73 | Wife | — | Illinois |
| 68 | M. Alice Bennett | 58 | Head | — | Illinois |
| 69 | Elizabeth Dunbar | 72 | Head | — | Illinois |
| 70 | Phar Dunbar | 48 | Son | Laborer | Illinois |
| 71 | Minnie Cearlock | 70 | Head | — | Illinois |
| 72 | Homer Cearlock | 47 | Son | Laborer | Illinois |
| 73 | Everett Cearlock | 44 | Son | Laborer | Illinois |
| 74 | Glenn Staples | 31 | Head | Barber | Illinois |
| 75 | Carrie Staples | 24 | Wife | Beauty Operator | Illinois |
| 76 | Charles Frodin | 44 | Head | Laborer | Illinois |
| 77 | May Frodin | 43 | Wife | — | Illinois |
| 78 | Leroy Frodin | 24 | Son | Laborer | Illinois |
| 79 | Opal Frodin | 23 | Daughter | — | Illinois |
| 80 | Hazel Frodin | 20 | Daughter | — | 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)