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Mary Lopez — 1940 US Census Record
Linked across censuses1940 United States Federal Census · San-Bernardino-County, California
Our Model Tree links this Mary Lopez across the 1930 and 1940 US Censuses in San-Bernardino-County, California (XGBoost, ~Confirmed) — first a daughter (b.~1921), then head of a 6-person household.
Age 19
b. ~1921
Female
Daughter
Born: California
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | San-Bernardino-County, California |
| Surname | Lopez |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | California |
| 1935 Residence (City) | San Bernardino City |
| 1935 Residence (County) | San Bernardino |
| Additional Details | |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
| Township / Ward | San Bernardino City |
| Est. Birth Year | ~1921 |
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 |
|---|---|---|---|---|
| Santos Sanchez | Head | — | 40 | ~1900 |
| Juanita Sanchez | Spouse | — | 43 | ~1897 |
| Ralph Lopez | Son | — | 14 | ~1926 |
| Bernardo Ontiveros | Son | — | 14 | ~1926 |
| Mary Lopez | Daughter | — | 19 | ~1921 |
| Henry Ontiveros | Son | — | 13 | ~1927 |
Census Appearances
1930
San Bernardino, …
Daughter, age 11
San Bernardino, California · implied b. ~1919 — 15 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Lopez |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | Mexican |
| Age | 11 |
| Marital Status | Single |
| Birthplace | California |
| Father's Birthplace | Mexico |
| Mother's Birthplace | Mexico |
| Can Read/Write | Yes |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
1940
San-Bernardino-County, California
Daughter, age 19
San-Bernardino-County, California · implied b. ~1921 — 6 household members
| Surname | Lopez |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | California |
| 1935 Residence (City) | San Bernardino City |
| 1935 Residence (County) | San Bernardino |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
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 Lopez across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Lopez
Daughter · 1940 · age 19 · b. ~1921 · California
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Sibling
Bernardo Ontiveros
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ralph Lopez
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Henry Ontiveros
Sibling · 1940 · age 13
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 — San-Bernardino-County, California
Open full size
1940 US Federal Census — San-Bernardino-County, California
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00293-00650)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Joe Jr Hernandez | 5 | Son | — | California |
| 42 | Carlos Hernandez | 3 | Son | — | California |
| 43 | Christina Hernandez | 1 | Daughter | — | California |
| 44 | Anacianio|Anaciano Sandoval | 69 | Head | — | New Mexico |
| 45 | Hilaria Sandoval | 68 | Wife | — | New Mexico |
| 46 | Jose R Aguilar | 43 | Head | Proprietor | Mexico |
| 47 | Maria Aguilar | 37 | Wife | Co-Proprietor | Mexico |
| 48 | Sofia E Aguilar | 14 | Daughter | — | California |
| 49 | John Aguilar | 9 | Son | — | California |
| 50 | Alice Aguilar | 7 | Daughter | — | California |
| 51 | Martha Aguilar | 4 | Daughter | — | California |
| 52 | Francesca Aguilar | 54 | Law | — | Mexico |
| 53 | Antonio Aguilar | 64 | Head | — | Mexico |
| 54 | Felicia Aguilar | 61 | Wife | — | Mexico |
| 55 | Anita Ramirez | 19 | Granddaughter | Seamstress | California |
| 56 | Rebecca Ramirez | 15 | Granddaughter | — | California |
| 57 | Nieves Pineda | 40 | Head | Mechanic Helper | Mexico |
| 58 | Leija Pineda | 37 | Wife | — | Mexico |
| 59 | Evangelina Pineda | 14 | Daughter | — | California |
| 60 | Inocente Pineda | 13 | Son | — | California |
| 61 | Maria Pineda | 12 | Daughter | — | California |
| 62 | Froylan Pineda | 9 | Son | — | California |
| 63 | Enos Pineda | 7 | Daughter | — | California |
| 64 | Joseph R Baca | 36 | Head | Auto Mechanic | California |
| 65 | Santos Sanchez | 40 | Head | Laborer | Mexico |
| 66 | Juanita Sanchez | 43 | Wife | — | Mexico |
| 67 | Mary Lopez THIS PERSON | 19 | Daughter | — | California |
| 68 | Ralph Lopez | 14 | Son | — | California |
| 69 | Bernardo Ontiveros | 14 | Son | — | California |
| 70 | Henry Ontiveros | 13 | Son | — | California |
| 71 | Marcos Gonzales | 39 | Head | Boiler Maker Helper | Mexico |
| 72 | Margarita Gonzales | 35 | Wife | — | California |
| 73 | Maria Flores | 16 | Mother-in-law | — | California |
| 74 | Alice Gonzales | 14 | Neice | — | Colorado |
| 75 | Frank Arroyo | 20 | Lodger | Cement Work | California |
| 76 | Aurelio Leon | 54 | Head | Machine Shop Helper | Mexico |
| 77 | Andres Leon | 40 | Wife | — | Mexico |
| 78 | Louis Leon | 31 | Son | Orange Picker | California |
| 79 | Margaret Leon | 28 | Daughter | — | California |
| 80 | Stephen Leon | 28 | Son | Orange Picker | California |
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)