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Mary Mcgrath — 1930 US Census Record
Model Tree available1930 United States Federal Census · Cook, Illinois
Our Model Tree links this Mary Mcgrath across the 1920, 1930 and 1940 US Censuses in Cook, Illinois (XGBoost, ~Confirmed), with identified parents Roger & Agatha — first a daughter (b.~1913), then head of a 7-person household.
Age 17
b. ~1913
Female
Daughter
Born: Illinois
Single
1930 Census Record Details
| Census Year | 1930 |
| Location | Cook, Illinois |
| Surname | McGrath |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Additional Details | |
| Occupation | Operator |
| Industry | Telephone |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Operator |
| Township / Ward | Chicago |
| Est. Birth Year | ~1913 |
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.
7 people recorded at the same address in the 1930 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Agatha Mcgrath | Daughter | — | 7 | ~1923 |
| Mary Mcgrath | Daughter | — | 17 | ~1913 |
| Agatha Mcgrath | Head | — | 43 | ~1887 |
| Harold Mcgrath | Son | — | 19 | ~1911 |
| Ray Mcgrath | Son | — | 14 | ~1916 |
| Edward Mcgrath | Son | — | 16 | ~1914 |
| Leo Mcgrath | Son | — | 11 | ~1919 |
Census Appearances
1920
Cook, Illinois
Daughter, age 7
Cook, Illinois · implied b. ~1913 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McGrath |
| Given Name | Mary C. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 7 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Cook, Illinois
Daughter, age 17
Cook, Illinois · implied b. ~1913 — 7 household members
| Surname | McGrath |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Operator |
| Industry | Telephone |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Other, age 28
Cook-County, Illinois · implied b. ~1912 — 11 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McGreat |
| Given Name | Mary Maude Sister |
| Relationship to Head | Sister |
| Sex | F |
| Color / Race | White |
| Age | 28 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Occupation | Teacher |
| Industry | Prop School |
| Class of Worker | PW |
| Hours Worked | 64 |
| Income (1939) | 420 |
| Highest Grade | C 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 Mcgrath across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Roger Mcgrath (~0.92 confidence) and mother Agatha Mcgrath (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Roger Mcgrath
b. ~1878
Source father
● Household
· direct · ~0.92
Mother
Agatha Mcgrath
b. ~1886
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Mcgrath
Daughter · 1930 · age 17 · b. ~1913 · Illinois
★ You are viewing this record
Sibling
Agatha Mcgrath
Sibling · 1930 · age 7
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Harold Mcgrath
Sibling · 1930 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Edward Mcgrath
Sibling · 1930 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Leo Mcgrath
Sibling · 1930 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ray Mcgrath
Sibling · 1930 · 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
1930 US Federal Census — Cook, Illinois
Open full size
1930 US Federal Census — Cook, Illinois
Page Contents
49 people indexed on this census page (ia:1930:illinoiscensus00reel451:0783)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 51 | Jerome Sommelsdorf | 38 | Head | Carpenter | Czechoslovakia |
| 52 | Antonia Sommelsdorf | 36 | Wife | None | Illinois |
| 53 | Alice Sommelsdorf | 14 | Daughter | None | Illinois |
| 54 | Geraldine Sommelsdorf | 4 | Daughter | None | Illinois |
| 55 | Anna Horat | 47 | Head | None | Illinois |
| 56 | Richard Horat | 22 | Son | Service Man | Illinois |
| 57 | George Horat | 20 | Son | None | Illinois |
| 58 | William Jackkel | 72 | Father | None | Germany |
| 59 | Frank Rostke | 33 | Head | Demonstrator | Illinois |
| 60 | Mary Rostke | 35 | Wife | None | Illinois |
| 61 | Francis Rostke | 3 | Son | None | Illinois |
| 62 | Robert Rostke | 2 | Son | None | Illinois |
| 63 | Mary O'Regan | 51 | Head | None | Kentucky |
| 64 | John O'Regan | 48 | Son | None | Illinois |
| 65 | Walter O'Regan | 32 | Son | Auditor | Illinois |
| 66 | Loretta O'Regan | 19 | Granddaughter | None | Illinois |
| 67 | Mike Tomaszewski | 62 | Head | Finisher | Poland |
| 68 | Antonia Tomaszewski | 54 | Wife | None | Poland |
| 69 | Mary Tomaszewski | 22 | Daughter | Packer | Illinois |
| 70 | Stanley Tomaszewski | 21 | Son | Machinist | Illinois |
| 71 | Lillian Tomaszewski | 19 | Daughter | Machinist | Illinois |
| 72 | Bruno Tomaszewski | 12 | Son | None | Illinois |
| 73 | Harold Sutter | 27 | Head | Mechanic | Illinois |
| 74 | Mattie Sutter | 27 | Wife | None | Illinois |
| 75 | Harold Jr. Sutter | 1 | Son | None | Illinois |
| 76 | Julia Brzozowski | 59 | Mother-in-law | None | Poland |
| 77 | Agatha Mcgrath | 43 | Head | None | Ireland |
| 78 | Harold Mcgrath | 19 | Son | Mail Tender | Illinois |
| 79 | Mary Mcgrath THIS PERSON | 17 | Daughter | Operator | Illinois |
| 80 | Edward Mcgrath | 16 | Son | Messenger | Illinois |
| 81 | Ray Mcgrath | 14 | Son | None | Illinois |
| 82 | Leo Mcgrath | 11 | Son | None | Illinois |
| 83 | Agatha Mcgrath | 7 | Daughter | None | Illinois |
| 84 | Frank Chmielewski | 59 | Head | Laborer | Poland |
| 85 | Martha Chmielewski | 56 | Wife | None | Poland |
| 86 | Frank Jr. Chmielewski | 24 | Son | Mechanic | Illinois |
| 87 | Eddie Chmielewski | 22 | Son | Photographer | Illinois |
| 88 | Francis Chmielewski | 18 | Daughter | Machine Op | Illinois |
| 89 | Stanley Chmielewski | 16 | Son | Errand Boy | Illinois |
| 90 | Milo Ritchey | 26 | Head | Machinist | So. Dakota |
| 91 | Mary Ritchey | 24 | Wife | None | Ireland |
| 92 | Maud E. Ritchey | 2 | Daughter | None | Illinois |
| 93 | James Ritchey | 1 | Son | None | Illinois |
| 94 | John Speranza | 53 | Head | Carrier | Italy |
| 95 | Mary Speranza | 43 | Wife | None | Italy |
| 96 | John Jr. Speranza | 21 | Son | Bricklayer | Illinois |
| 97 | James Speranza | 18 | Son | Errand Boy | Illinois |
| 98 | Robert Speranza | 16 | Son | None | Illinois |
| 99 | William Speranza | 13 | Son | None | Illinois |
Pedigree Summary
Mary + 5 siblings
Gen 1 · 2 parents
~0.92
Max depth 4 (1900–1950 window)
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1930 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)