Unable to find Rachel Mumford on the 1930 census but here she is on the 1920 living with her brother.
1920 Illinois, Cook County, Chicago, ED#1453, Page 188A, 1/2,3/1920:
Rachel (Mrs.) Mumford, head, 35yo, widowed, Imm. Unknown, Norway, No Occupation
Elof Robarth, brother, 30yo, Imm.Unknown, Norway, Mechanic/Machine Shop
Believe the following is your William O. Mumford....
1910 Illinois, Cook County, Chicago, ED#1415, Page 87A, 4/20/1910:
William B. Mumford, head, 41yo, widowed, MI PA NY, Broker/Grain
Memar R., daughter, 17yo, IL MI NY
Haleen B., daughter, 14yo, IL MI NY
Margaret T., daughter, 12yo, IL MI NY
???? R. Smith, housekeeper, 35yo, NY NY NY, Housekeeper/Private Family
Linnet? Hedstrom, servant, 19yo, Sweden, Imm.1909, Servant/Private Family
(Servants are indexed as Susan R. Smith and Linnea Hedstrom)
1900 Illinois, Cook County, Chicago, Calumet Township, ED#986, Page 100A, 6/12/1900:9860 Prospect Avenue
Wm. O. Mumford, head, 30yo, 3/1870, M/8yrs, MI PA NY, Boarder
Martha, wife, 30yo, 2/1870, M/8yrs, 3 children/3 living, NY NY Ireland
Memae?, daughter, 7yo, 3/1893, IL MI NY
Helene, daughter, 4yo, 10/1895, IL MI NY
Margarett, daughter, 2yo, 4/1898, IL MI NY
Mary Krohn, servant, 23yo, 10/1877, IL Germany IL, Servant
Illinois Deaths:Cook County
Wm. O. Mumford, 46yo, d.8/22/1915 Englewood Hospital.Born Niles Michigan, unknown date.Married.Resident of Chicago 40 years.Father Wm.R. Mumford born New York, mother Charlotte Hamilton born New York.Occupation Broker.
Informant Clarence Mumford.Cause of death "delirium tremens".
*Wikipedia describes the aforementioned as severe withdrawal from alcohol which is sometimes fatal.
Martha (Mrs. Wm. O.) Mumford, 37yo, d.8/20/1907 in Englewood Hospital, 4 days in hospital
Born New York, Father New York, Mother Ireland
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