I was sorry to hear of the loss of your mother. Unfortunately, at least in regard to bringing a case, the finding of "natural causes" would hinder such an effort. In addition, there appears to be a lot of self abuse and known (by you?) adverse conditions and lack of self care. The fact that medications may have been stockpiled and are missing could be addressed through the medical examiner or coroner. They may collect and dispose of such medications that are prescribed to the deceased.
I cannot imagine a connection to the old case you referenced. However, much investigation and study may prove otherwise. It would be very expensive to explore.
I suggest you seek an interview with an attorney in Washington to discuss this personally and put your concerns to rest.
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