MD
Mary Dempsey — 1940 US Census Record
Model Tree available1940 United States Federal Census · Peoria-County, Illinois
Our Model Tree links this Mary Dempsey across the 1920, 1930 and 1940 US Censuses in Peoria-County, Illinois (XGBoost, ~Confirmed), with identified parents John & John — first a daughter (b.~1919), then head of a 4-person household.
Age 21
b. ~1919
Female
Daughter
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Peoria-County, Illinois |
| Surname | Dempsey |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Peoria city |
| 1935 Residence (County) | Peoria |
| Additional Details | |
| Occupation | packer |
| Industry | Packing Co. |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1000 |
| Highest Grade | H-4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Packer |
| Township / Ward | Peoria City |
| Est. Birth Year | ~1919 |
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 |
|---|---|---|---|---|
| Mary Dempsey | Daughter | — | 21 | ~1919 |
| John Dempsey | Head | — | 51 | ~1889 |
| Jessie Dempsey | Spouse | — | 53 | ~1887 |
| Robert Dempsey | Son | — | 23 | ~1917 |
Census Appearances
1920
Peoria, Illinois
Daughter, age 1
Peoria, Illinois · implied b. ~1919 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Dempsey |
| Given Name | Mary |
| Relationship to Head | daughter |
| Sex | F |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Occupation | none |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Peoria, Illinois
Daughter, age 11
Peoria, Illinois · implied b. ~1919 — 10 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Dempsey |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Peoria-County, Illinois
Daughter, age 21
Peoria-County, Illinois · implied b. ~1919 — 4 household members
| Surname | Dempsey |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Peoria city |
| 1935 Residence (County) | Peoria |
| Occupation | packer |
| Industry | Packing Co. |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1000 |
| Highest Grade | H-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 Mary Dempsey across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father John Dempsey (~0.92 confidence) and father John Dempsey (~0.92 confidence) and mother Theresa Dempsey (~0.92 confidence) and mother Theresa Dempsey (~0.92 confidence) and mother Jessie Dempsey (~0.92 confidence) and father John Dempsey (~0.92 confidence) and mother Rose Groters (~0.60 confidence). The pedigree spans 1 generation with 7 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.87
Father
John Dempsey
b. ~1868
Source father
● Household
· direct · ~0.92
Father
John Dempsey
b. ~1872
Source father
● Household
· direct · ~0.92
Mother
Theresa Dempsey
b. ~1875
Source mother
● Household
· direct · ~0.92
Mother
Theresa Dempsey
b. ~1885
Source mother
● Household
· direct · ~0.92
Mother
Jessie Dempsey
b. ~1887
Source mother
● Household
· direct · ~0.92
Father
John Dempsey
b. ~1889
Source father
● Household
· direct · ~0.92
Mother
Rose Groters
b. ~1910
Source mother
● Household
· direct · ~0.6
This person
Anchor record
Mary Dempsey
Daughter · 1940 · age 21 · b. ~1919 · Illinois
★ You are viewing this record
Sibling
Robert Dempsey
Sibling · 1940 · age 23
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 — Peoria-County, Illinois
Open full size
1940 US Federal Census — Peoria-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00920-00095)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Mary Murphy | 48 | Head | Operator | Illinois |
| 2 | Elizabeth Murphy | 38 | Daughter | Bookkeeper | Illinois |
| 3 | Loren Mansfield | 42 | Head | Labour | Michigan |
| 4 | Erma Mansfield | 42 | Wife | — | Illinois |
| 5 | Emma Ging | 71 | Mother-in-law | — | Illinois |
| 6 | Frank Frederick | 55 | Head | Inspector | Illinois |
| 7 | Otis Frederick | 49 | Brother | Salesman | Illinois |
| 8 | John E. Dempsey | 51 | Head | Legal Clerk | Illinois |
| 9 | Jessie Dempsey | 53 | Wife | Clerk | Illinois |
| 10 | Robert Dempsey | 23 | Son | Messenger | Illinois |
| 11 | Mary Dempsey THIS PERSON | 21 | Daughter | Packer | Illinois |
| 12 | Harold Correll | 27 | Head | — | Illinois |
| 13 | Esther Correll | 26 | Wife | — | Illinois |
| 14 | Janet E. Correll | 3 | Daughter | — | Illinois |
| 15 | Edgar Bennett | 28 | Head | Shipping Clerk | Illinois |
| 16 | Lacey Bennett | 27 | Wife | — | Illinois |
| 17 | Evelyn Bennett | 9 | Daughter | — | Illinois |
| 18 | Donald Bennett | 7 | Son | — | Illinois |
| 19 | Elizabeth Bennett | 2 | Daughter | — | Illinois |
| 20 | Ray Bennett | 22 | Head | Welder | Illinois |
| 21 | Gladys Bennett | 32 | Sister | Housekeeper | Illinois |
| 22 | Harold Bennett | 19 | Brother | Waiter | Illinois |
| 23 | George Spinks | 49 | Head | Salesman | Missouri |
| 24 | Margaret Spinks | 44 | Wife | Operator | Illinois |
| 25 | Lyle Spinks | 17 | Son | Dishwasher | Illinois |
| 26 | Katherine Gow | 69 | Mother | — | Illinois |
| 27 | Peter J. Montgomery | 36 | Head | Motor Bus Conductor | Illinois |
| 28 | Tommie Montgomery | 32 | Wife | — | Arkansas |
| 29 | Jack Montgomery | 1 | Son | — | Arkansas |
| 30 | Frank Bunco | 24 | Head | Beauty Shop | Illinois |
| 31 | Geraldine Bunco | 20 | Wife | Proprietor | Illinois |
| 32 | Franklin Bunco | 1 | Son | — | Illinois |
| 33 | Anton Wiesling | 62 | Head | Tailor | Germany |
| 34 | Mary Wiesling | 51 | Wife | — | Illinois |
| 35 | Robert Wiesling | 30 | Son | — | Illinois |
| 36 | Francesco Frasco | 53 | Head | Laborer | Italy |
| 37 | Anna Frasco | 43 | Wife | — | Italy |
| 38 | Louis Roberts | 46 | Head | Fireman | Illinois |
| 39 | Ellen Roberts | 49 | Wife | — | England |
| 40 | William Voltz | 50 | Head | Blacksmith | Kentucky |
Pedigree Summary
Mary + 1 sibling
Gen 1 · 7 parents
~0.87
Max depth 4 (1900–1950 window)
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)