MH
Mary Hennessy — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this Mary Hennessy across the 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed) — first a daughter (b.~1927), then head of a 6-person household.
Age 13
b. ~1927
Female
Daughter
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | Hennessy |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Highest Grade | No 7 |
| 1935 Residence | Same Place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Township / Ward | Boston City |
| Est. Birth Year | ~1927 |
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.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Angeline Hennessy | Daughter | — | 16 | ~1924 |
| Edward Hennessy | Head | — | 65 | ~1875 |
| Mary Hennessy | Daughter | — | 13 | ~1927 |
| Marguerite Hennessy | Spouse | — | 38 | ~1902 |
| Agnes Hennessy | Daughter | — | 14 | ~1926 |
| Edward Hennessy | Son | — | 7 | ~1933 |
Census Appearances
1930
Suffolk, Massachusetts
Other, age 2
Suffolk, Massachusetts · implied b. ~1928 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Hennessey |
| Given Name | Mary |
| Relationship to Head | granddaughter |
| Sex | F |
| Color / Race | White |
| Age | 2 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland North |
| Mother's Birthplace | Massachusetts |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Daughter, age 13
Suffolk-County, Massachusetts · implied b. ~1927 — 6 household members
| Surname | Hennessy |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Highest Grade | No 7 |
| 1935 Residence | Same Place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
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 Hennessy across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Hennessy
Daughter · 1940 · age 13 · b. ~1927 · Massachusetts
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Sibling
Edward Hennessy
Sibling · 1940 · age 7
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Angeline Hennessy
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Agnes Hennessy
Sibling · 1940 · age 14
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 — Suffolk-County, Massachusetts
Open full size
1940 US Federal Census — Suffolk-County, Massachusetts
Page Contents
37 people indexed on this census page (nara:1940:m-t0627-01666-00421)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Patricia D. White | 3 | Daughter | — | Massachusetts |
| 42 | John P. White | 0 | Son | — | Massachusetts |
| 43 | George Lyons | 65 | Lodger | Helper | Rhode Island |
| 44 | James Mclaughlin | 32 | Lodger | Second Cook | Michigan |
| 45 | Joseph Halenbaek | 43 | Lodger | Laborer | Massachusetts |
| 46 | Clarence H. Snowden | 53 | Head | Proprietor | Canada Eng |
| 47 | Sarah E. Snowden | 53 | Wife | — | Massachusetts |
| 48 | George H. Snowden | 22 | Son | Coil Maker | Massachusetts |
| 49 | Ellen Hicks | 86 | Mother | — | Canada Eng |
| 50 | Ellen Sullivan | 80 | Sister | — | Canada Eng |
| 51 | John D. Armstrong | 60 | Head | Cooper | New Hampshire |
| 52 | Margaret A. Armstrong | 61 | Wife | — | New Hampshire |
| 53 | R. Charles Columbia | 33 | Head | Water Tender Class 1 | Puerto Rico |
| 54 | Ethel E. Columbia | 25 | Wife | — | Massachusetts |
| 55 | Rita Columbia | 3 | Daughter | — | Massachusetts |
| 56 | Charles R. Columbia | 2 | Son | — | Massachusetts |
| 57 | John R. Sersanti | 30 | Head | Photo Engraver | Italy |
| 58 | Lillian Sersanti | 21 | Wife | — | Massachusetts |
| 59 | Frances Sersanti | 3 | Daughter | — | Massachusetts |
| 60 | Donald L. Sersanti | 1 | Son | — | Massachusetts |
| 61 | Catherine H. Mcnally | 58 | Head | — | Massachusetts |
| 62 | John P. Mcnally | 24 | Son | Sail Maker | Massachusetts |
| 63 | James M. Brown | 28 | Head | Electrician'S Helper | Massachusetts |
| 64 | Mary Brown | 23 | Wife | — | Massachusetts |
| 65 | Margaret Brown | 3 | Daughter | — | Massachusetts |
| 66 | Madeline Brown | 2 | Daughter | — | Massachusetts |
| 67 | John J. Eagan | 59 | Head | Night Watchman | Massachusetts |
| 68 | Anna E. Eagan | 58 | Wife | — | Massachusetts |
| 69 | Walter H. Eagan | 23 | Son | Kitchen Man | Massachusetts |
| 70 | John Eagan | 36 | Son | Window Cleaner | Massachusetts |
| 71 | Margaret Eagan | 68 | Sister | Laundress | Massachusetts |
| 72 | Edward Hennessy | 65 | Head | Contract Plumber | Massachusetts |
| 73 | Marguerite Hennessy | 38 | Wife | — | Massachusetts |
| 74 | Angeline Hennessy | 16 | Daughter | — | Massachusetts |
| 75 | Agnes Hennessy | 14 | Daughter | — | Massachusetts |
| 76 | Mary Hennessy THIS PERSON | 13 | Daughter | — | Massachusetts |
| 77 | Edward Hennessy | 7 | Son | — | Massachusetts |
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)