I'm not related to this family but will be going to Mt. Clemens Public Library in a couple of weeks and if you like I can look for a death notice(s) for you for Bill, Helen Bushey in your not from the Macomb County Michigan area.
Also I found a reference to a Mary Bushey HAWN that died either Jan 1 or 2 nd 1956 and was 85 years old. Could this be your Great Aunt Mary?
Please contact me via email if you are still needing any or all the information I described