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Mary Mcmahon — 1920 US Census Record
Linked across censuses1920 United States Federal Census · Hamilton, Illinois
Our Model Tree links this Mary Mcmahon across the 1920 and 1930 US Censuses in Hamilton, Illinois (XGBoost, ~Confirmed) — first a daughter (b.~1916), then head of a 9-person household.
Age 4
b. ~1916
Female
Daughter
Born: Illinois
Single
1920 Census Record Details
| Census Year | 1920 |
| Location | Hamilton, Illinois |
| Surname | McMahon |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Additional Details | |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Crook Township |
| Est. Birth Year | ~1916 |
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.
9 people recorded at the same address in the 1920 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Mcmahon | Daughter | — | 4 | ~1916 |
| Sadie Mcmahon | Daughter | — | 16 | ~1904 |
| Edna Mcmahon | Daughter | — | 13 | ~1907 |
| Matt Mcmahon | Head | — | 44 | ~1876 |
| William Mcmahon | Son | — | 2 | ~1918 |
| Paul Mcmahon | Son | — | 9 | ~1911 |
| Coy Mcmahon | Son | — | ~1920 | |
| Wayne Mcmahon | Son | — | 11 | ~1909 |
| Blanch Mcmahon | Spouse | — | 34 | ~1886 |
Census Appearances
1920
Hamilton, Illinois
Daughter, age 4
Hamilton, Illinois · implied b. ~1916 — 9 household members
| Surname | McMahon |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Hamilton, Illinois
Daughter, age 14
Hamilton, Illinois · implied b. ~1916 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McMahan |
| Given Name | Mary V. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 14 |
| 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 |
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 Mcmahon across 2 US Census years (1920 and 1930) in Hamilton, Illinois, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mcmahon
Daughter · 1920 · age 4 · b. ~1916 · Illinois
★ You are viewing this record
Sibling
Edna Mcmahon
Sibling · 1920 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Wayne Mcmahon
Sibling · 1920 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Paul Mcmahon
Sibling · 1920 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Sadie Mcmahon
Sibling · 1920 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Coy Mcmahon
Sibling · 1920 · age
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
William Mcmahon
Sibling · 1920 · age 2
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
1920 US Federal Census — Hamilton, Illinois
Open full size
1920 US Federal Census — Hamilton, Illinois
Page Contents
50 people indexed on this census page (ia:1920:14thcensusofpopu366unit:0822)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Joseph Mitchell | 58 | Head | Farmer | Illinois |
| 2 | Hannah J Mitchell | 57 | Wife | — | Indiana |
| 3 | Ella M Mitchell | 31 | Daughter | — | Illinois |
| 4 | Thea G Mitchell | 27 | Daughter | — | Illinois |
| 5 | Joseph M Mitchell | 17 | Son | Farm Labor | Illinois |
| 6 | James L Mitchell | 15 | Son | — | Illinois |
| 7 | Robert F Mitchell | 13 | Son | — | Illinois |
| 8 | Mary C Mccluskey | 6 | Grand Daughter | — | Illinois |
| 9 | Hazel R Mccluskey | 4 | Grand Daughter | — | Illinois |
| 10 | John P Abney | 33 | Boarder | — | Illinois |
| 11 | Douglas P Mitchell | 22 | Head | Farmer | Illinois |
| 12 | John Mccarthy | 62 | Head | Farmer | Illinois |
| 13 | Lizzie M Mccarthy | 61 | Wife | — | Indiana |
| 14 | Ernest F Mccarthy | 23 | Son | Farmer | Illinois |
| 15 | Thomas W Yeats | 72 | Head | Farmer | Illinois |
| 16 | Angeline Mcdaniel | 56 | Housekeeper | Housekeeper | Illinois |
| 17 | Grant Little | 56 | Head | Farmer | Ohio |
| 18 | Irvina E Little | 49 | Wife | — | Illinois |
| 19 | Josephine Little | 18 | Daughter | — | Illinois |
| 20 | Grant Jr Little | 13 | Son | — | Illinois |
| 21 | Matt J Mcmahon | 44 | Head | Farmer | Illinois |
| 22 | Blanch Mcmahon | 34 | Wife | — | Illinois |
| 23 | Sadie G Mcmahon | 16 | Daughter | — | Illinois |
| 24 | Edna E Mcmahon | 13 | Daughter | — | Illinois |
| 25 | Wayne H Mcmahon | 11 | Son | — | Illinois |
| 26 | Paul M Mcmahon | 9 | Son | — | Illinois |
| 27 | Mary Mcmahon THIS PERSON | 4 | Daughter | — | Illinois |
| 28 | William B Mcmahon | 2 | Son | — | Illinois |
| 29 | Coy E Mcmahon | 0 | Son | — | Illinois |
| 30 | Arthur R Martin | 39 | Head | Farmer | Illinois |
| 31 | Nellie M Martin | 30 | Wife | — | Illinois |
| 32 | John W Mitchell | 18 | Son in Law | Farm Labor | Illinois |
| 33 | Charles F Mitchell | 15 | Son in Law | Farm Labor | Illinois |
| 34 | Nolan W Mitchell | 9 | Son in Law | — | Illinois |
| 35 | Jess Cartmill | 40 | Head | Farmer | Illinois |
| 36 | Elma J Cartmill | 27 | Wife | — | Illinois |
| 37 | Arthur Cartmill | 6 | Son | — | Illinois |
| 38 | Raymond U Cartmill | 3 | Son | — | Illinois |
| 39 | Lillie E Cartmill | 1 | Daughter | — | Illinois |
| 40 | James G Childers | 42 | Head | Farmer | Illinois |
| 41 | Annie Childers | 38 | Wife | — | Illinois |
| 42 | Lloyd E Pris | 26 | Head | Farmer | Illinois |
| 43 | Ruby C Pris | 24 | Wife | — | Illinois |
| 44 | Riley D Dorman | 31 | Head | Farmer | Illinois |
| 45 | Ada E Dorman | 34 | Wife | — | Illinois |
| 46 | Jessie B Dorman | 9 | Son | — | Illinois |
| 47 | Joseph L Dorman | 8 | Son | — | Illinois |
| 48 | Alma M Milam | 2 | Niece | — | Illinois |
| 49 | Clyde Milam | 31 | Head | Farmer | Illinois |
| 50 | Iva A Milam | 23 | Wife | — | Illinois |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1920 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)