Wilbur Chester Foster was born 24 Aug 1911 in Denver, Colorado, to Michael Andrew Foster (1865-1941) & Mary J Dickey (1868-1938).
Inmate: #66368 San Quentin Prison
Rec: 1 Apr 1941
Crime: Burglary 2nd Degree and 2 priors
Here are the newspaper articles I found.
He was also in Oregon State Prison as Inmate #14131, here's the newspaper article for 1936 for drunk driving and theft charges and stealing a car.
Wilbur was never married but he listed his sister Mabel as a contact on his prison records.
Claude Dell Foster
Elmer Bert Foster
Mable F Foster
Wilbur Chester Foster
His father married again 5 Jul 1939 in Yuma, AZ to Antonia May Taylor (1877–1944).
Wilbur was transferred to Folsom prison