Hi, What does their obituaries say? If you don't have the obituaries, you will find an obituary volunteer at Random Acts Genealogical Kindness. Go to raogk.org, read guidelines, choose Oregon, choose Coos County and choose Rhonda.
If you have the obituaries and where they are buried isn't mentioned, have you looked for them in findagrave.com?
Also you can contact the Coos Bay Family History Center, orgenweb.org/coos/his_gen.htm . Some groups have walked and indexed cemeteries in their county. Successful Searching!