The best I could find on a John Shedden born ca 1880 is…
1930 census Montclair, Essex County, NJ:
John S. Shedden, 49, born in Colorado, parents in Scotland
Anna R. 48, born in Ohio, parents in Germany and France
Mary L. 17, born in Washington (daughter)
1920 census Manhattan, NYC, NY:
John S. Shedden, 40, born in Washington (roomer)
(apparently Anna and daughter stayed behind in Washington, living with a sister Elizabeth Raff)
1910 census Spokane, WA:
John S. Shedden 29, born in Colorado
Anna F. 28, born in Ohio, married 1 yr
According to Washington birth records John S. & Anna Francis (Rapp) Shedden had two children: John Albert Dec 10, 1909 and Mary Louise Sept 12, 1911.
John Stephens Shedden's World War I and II draft cards show he was born Nov 19, 1880 in Browns Park, Colorado (both show Anna as his wife).
I did find a William Shedden, 35, born in Scotland, Sarah 25, born in England, Nellie 8, born in PA, Charles 6, born in PA, Anna 4, born in Iowa and William 2, born in Wyoming living in Rock springs, Sweetwater Co., WY. Living with them was William Paterson 20, born in England.
I found a Sarah Shedden in the 1910, 1920 and 1920 censuses living in the same location who would be the right age living with her widowed siste Alice. Her sister last name is different in each census but I suspect it is Kevile (based on the 1900 census showing her as the wife of Albert Kevile in the same location).
I also found death record info on a Sarah Jane Pater Shedden, born Aug 13, 1854, died Dec 20, 1940 in Boise, ID. Whether the Wyoming Sheddens had anything to do with John Shedden born in Colorado I don't know. It could be the family moved to Colorado and Sarah moved back after William died.
I could not find John in the 1900 census anywhere. For that matter I could not find Sarah or William under any spelling that would fit.
John and Francis Rapp were married on Feb 20, 1909: http://www.digitalarchives.wa.gov/ViewRecord.aspx?RID=BE7AFF73B0BA3BF4607F3F69F597683Fhttp://www.digitalarchives.wa.gov/ViewRecord.aspx?RID=BE7AFF73B0BA3BF4607F3F69F597683F