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Mary Mcdonnell — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Scott-County, Iowa
Our Model Tree links this Mary Mcdonnell across the 1930 and 1940 US Censuses in Scott-County, Iowa (XGBoost, ~Confirmed) — first a daughter (b.~1924), then head of a 5-person household.
Age 16
b. ~1924
Female
Daughter
Born: Iowa
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Scott-County, Iowa |
| Surname | McDonnell |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Davenport City |
| 1935 Residence (County) | Scott |
| Additional Details | |
| Income (1939) | 0 |
| Highest Grade | H-2 |
| 1935 Residence | Same place |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Township / Ward | Davenport City |
| Est. Birth Year | ~1924 |
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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Mcdonnell | Spouse | — | 39 | ~1901 |
| Harold Mcdonnell | Son | — | 12 | ~1928 |
| Richard Mcdonnell | Son | — | 18 | ~1922 |
| Mary Mcdonnell | Daughter | — | 16 | ~1924 |
| Joan Mcdonnell | Daughter | — | 8 | ~1932 |
Census Appearances
1930
Scott, Iowa
Daughter, age 5
Scott, Iowa · implied b. ~1925 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDonald |
| Given Name | Mary A. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 5 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Iowa |
| Occupation | none |
| Can Read/Write | Yes |
| Veteran | No |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Scott-County, Iowa
Daughter, age 16
Scott-County, Iowa · implied b. ~1924 — 5 household members
| Surname | McDonnell |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Davenport City |
| 1935 Residence (County) | Scott |
| Income (1939) | 0 |
| Highest Grade | H-2 |
| 1935 Residence | Same place |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
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 Mcdonnell across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Mcdonnell
Daughter · 1940 · age 16 · b. ~1924 · Iowa
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Sibling
Richard Mcdonnell
Sibling · 1940 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Harold Mcdonnell
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Joan Mcdonnell
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 — Scott-County, Iowa
Open full size
1940 US Federal Census — Scott-County, Iowa
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-01203-00736)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Mary Mcdonnell | 39 | Wife | — | Iowa |
| 42 | Richard Mcdonnell | 18 | Son | — | Iowa |
| 43 | Mary Mcdonnell THIS PERSON | 16 | Daughter | — | Iowa |
| 44 | Harold Mcdonnell | 12 | Son | — | Iowa |
| 45 | Joan Mcdonnell | 8 | Daughter | — | Iowa |
| 47 | Helen T. Lew | 69 | Head | — | Ireland |
| 48 | Thomas John Kerns | 67 | Brother | — | Ireland |
| 49 | Charles Christiansen | 53 | Head | Civil Engineer | Illinois |
| 50 | Sara Christiansen | 45 | Wife | — | Illinois |
| 51 | Gordon Christiansen | 15 | Son | — | Illinois |
| 52 | Dolores Christiansen | 22 | Daughter | — | Illinois |
| 53 | Joseph E. Wilson | 40 | Head | Linotype Operator | Kansas |
| 54 | Gladys Wilson | 40 | Wife | — | Missouri |
| 55 | Mary E. Strong | 76 | Roomer | — | Missouri |
| 56 | Julius Freund | 49 | Head | Salesman | Iowa |
| 57 | Lillian Freund | 45 | Wife | — | Iowa |
| 58 | Roger Brown | 25 | Head | Millwright | Iowa |
| 59 | Opal Brown | 25 | Wife | — | Missouri |
| 60 | Robert Brown | 3 | Son | — | Iowa |
| 61 | Elmer Armstrong | 29 | Head | Plasterer | Iowa |
| 62 | Lucile Armstrong | 27 | Wife | — | Iowa |
| 63 | Nellie Waters | 45 | Head | Saleslady | Illinois |
| 64 | Eloise Waters | 23 | Daughter | Nurse | Illinois |
| 65 | Eleanor Waters | 23 | Daughter | Nurse | Illinois |
| 66 | Thomas H. Watt | 36 | Head | Manager | Illinois |
| 67 | Leonore Watt | 30 | Wife | — | Illinois |
| 68 | Jack G. Watt | 9 | Son | — | Illinois |
| 69 | James M. Watt | 6 | Son | — | Illinois |
| 70 | Mazie Stokes | 58 | Head | Owner | Illinois |
| 71 | Bernice Stokes | 38 | Daughter | Office Clerk | Illinois |
| 72 | Leona Stokes | 28 | Daughter | Office Clerk | Illinois |
| 73 | George Wright | 32 | Head | Accountant | Iowa |
| 74 | Eleanor Wright | 31 | Wife | — | Iowa |
| 75 | George Wright | 6 | Son | — | Iowa |
| 76 | James Wright | 4 | Son | — | Iowa |
| 77 | John Swarm | 26 | Head | Salesman | Iowa |
| 78 | Julia Swarm | 26 | Wife | — | Iowa |
| 79 | Harry Franch | 46 | Head | Accountant | Iowa |
| 80 | Laura Franch | 48 | Wife | — | Iowa |
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)