I know you have been looking for this family for some time, and assume you know they lived in Los Angeles, 1920 census (Annie Schmidt, with sons Harold and Charles Nason). Reginald seems to have used Charles R. as an adult. He was living in LA in 1930, with wife, Helen, age 28, and a stepson, Earl Chapman.
Charles R. Nason, b. in Canada 11 June 1901, died in Los Angeles County 26 January 1985.His mother's maiden name was Hannaford, per death index.
You should be able to get an obit from the LA Times that would name survivors, if any.