I don't know if there were city directories for Sedro Wooley in that time period, but if there were, the local library should have copies. Scroll down to the bottom of this link, there is a link to contact the librarian. They wre usually willing to do a short search.http://www.ci.sedro-woolley.wa.us/Library/main.htm
You should also ask for a lookup in the Bellingham directories.
This link has death notices for Clemens wife Alida and his son Herberthttp://wagenweb.org/whatcom/wgsobits/deathsno_ny.htm
Obituary for grandson of Clemens and Alidahttp://www.peninsuladailynews.com/apps/pbcs.dll/article?AID=...