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Mary Mcdonnell — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Baltimore-City-County, Maryland
Our Model Tree links this Mary Mcdonnell across the 1930 and 1940 US Censuses in Baltimore-City-County, Maryland (XGBoost, ~Confirmed) — first a daughter (b.~1919), then head of a 9-person household.
Age 21
b. ~1919
Female
Daughter
Born: Maryland
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Baltimore-City-County, Maryland |
| Surname | McDonnell |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Maryland |
| 1935 Residence (City) | Baltimore City |
| 1935 Residence (County) | Baltimore City |
| Additional Details | |
| Industry | U |
| Highest Grade | No 0 |
| 1935 Residence | Same House |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
| Township / Ward | Baltimore 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.
9 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Elizabeth Mcdonnell | Daughter | — | 15 | ~1925 |
| Frances Mcdonnell | Daughter | — | 12 | ~1928 |
| Michael Mcdonnell | Head | — | 46 | ~1894 |
| Mary Mcdonnell | Daughter | — | 21 | ~1919 |
| Helen Mcdonnell | Daughter | — | 7 | ~1933 |
| Julia Mcdonnell | Spouse | — | 45 | ~1895 |
| Kathleen Mcdonnell | Daughter | — | 9 | ~1931 |
| Joseph Mcdonnell | Son | — | 26 | ~1914 |
| James Mcdonnell | Son | — | 17 | ~1923 |
Census Appearances
1930
Baltimore, Maryland
Daughter, age 10
Baltimore, Maryland · implied b. ~1920 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDonald |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Maryland |
| Father's Birthplace | Maryland |
| Mother's Birthplace | Germany |
| Can Read/Write | Yes |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
1940
Baltimore-City-County, Maryland
Daughter, age 21
Baltimore-City-County, Maryland · implied b. ~1919 — 9 household members
| Surname | McDonnell |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Maryland |
| 1935 Residence (City) | Baltimore City |
| 1935 Residence (County) | Baltimore City |
| Industry | U |
| Highest Grade | No 0 |
| 1935 Residence | Same House |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
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 21 · b. ~1919 · Maryland
★ You are viewing this record
Sibling
Frances Mcdonnell
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Kathleen Mcdonnell
Sibling · 1940 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
James Mcdonnell
Sibling · 1940 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Elizabeth Mcdonnell
Sibling · 1940 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Joseph Mcdonnell
Sibling · 1940 · age 26
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Helen Mcdonnell
Sibling · 1940 · age 7
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 — Baltimore-City-County, Maryland
Open full size
1940 US Federal Census — Baltimore-City-County, Maryland
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01517-00165)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Myrtle Sturmain | 37 | Wife | — | Maryland |
| 2 | William W. Furlong | 55 | Head | Station Agent | Maryland |
| 3 | Catherine B. Furlong | 52 | Wife | — | Maryland |
| 4 | Catherine M. Furlong | 26 | Daughter | Junior Clerk | Maryland |
| 5 | Genevieve Furlong | 16 | Daughter | — | Maryland |
| 6 | Rose Sturmain | 45 | Sister-in-law | — | Maryland |
| 7 | Michael Mcdonnell | 46 | Head | Laborer | Ireland |
| 8 | Julia Mcdonnell | 45 | Wife | — | Ireland |
| 9 | Joseph Mcdonnell | 26 | Son | Laborer | Maryland |
| 10 | Mary Mcdonnell THIS PERSON | 21 | Daughter | — | Maryland |
| 11 | James Mcdonnell | 17 | Son | — | Maryland |
| 12 | Elizabeth Mcdonnell | 15 | Daughter | — | Maryland |
| 13 | Frances Mcdonnell | 12 | Daughter | — | Maryland |
| 14 | Kathleen Mcdonnell | 9 | Daughter | — | Maryland |
| 15 | Helen Mcdonnell | 7 | Daughter | — | Maryland |
| 16 | Katherine Mcnally | 43 | Head | Servant | Maryland |
| 17 | Bernard Manning | 47 | Head | Brakeman | Maryland |
| 18 | Anna Manning | 39 | Wife | — | Maryland |
| 19 | Bernard Jr. Manning | 20 | Son | Helper | Maryland |
| 20 | James Manning | 18 | Son | Messenger | Maryland |
| 21 | William Manning | 16 | Son | — | Maryland |
| 22 | Raymond Manning | 14 | Son | — | Delaware |
| 23 | Thomas Manning | 8 | Son | — | Maryland |
| 24 | James J. Keenan | 51 | Head | Chef | Ireland |
| 25 | Agnes Keenan | 44 | Wife | — | Maryland |
| 26 | Ellen Keenan | 21 | Daughter | Servant | Maryland |
| 27 | Thomas Keenan | 20 | Son | Laborer | Maryland |
| 28 | Mary Keenan | 18 | Daughter | — | Maryland |
| 29 | Francis Keenan | 17 | Son | — | Maryland |
| 30 | Catherine Keenan | 15 | Daughter | — | Maryland |
| 31 | Edith Keenan | 12 | Daughter | — | Maryland |
| 32 | Theresa Keenan | 10 | Daughter | — | Maryland |
| 33 | Vincent Keenan | 9 | Son | — | Maryland |
| 34 | Agnes M. Keenan | 5 | Daughter | — | Maryland |
| 35 | James P. Byrne | 45 | Brother-in-law | Orderly | Maryland |
| 36 | Margaret Theopold | 60 | Lodger | Clerk | Maryland |
| 37 | Frank Walms | 39 | Head | — | Maryland |
| 38 | Elizabeth C. Walms | 42 | Wife | — | Maryland |
| 39 | Louis Walms | 19 | Son | — | Maryland |
| 40 | Katherine Walms | 16 | Daughter | — | Maryland |
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)