Geez, how many ways is her self-medication dangerous?
The "prednisone" may not be pure, i.e. adulterated. If it's pure, it may have lost potency over the several years. Ignoring those factors, it'll elevate her blood sugar (she's a Type 2 diabetic, IIRC), cause weight gain, mess with her sleep. If she does have to receive treatment with medications, being on steroids could complicate medication choices, assuming she tells her doctor (and if she doesn't tell her doctor ...). On the other side, prednisone, like other steroids, is not something you stop cold. A week or two of tapering off is common practice.
In all seriousness, she should have her doctor looking into: Eli Lilly's LY-CoV555 (bamlanivimab) monoclonal antibody monotherapy treatment or LY-CoV555 with LY-CoV016 monoclonal antibodies combination treatment; or Regeneron's REGN-COV2 monoclonal antibodies combination treatment; convalescent plasma antibody treatment.
> Convalescent plasma antibody treatment received Emergency Use Authorization (EUA) from the FDA in late August (after being tested with ~70K patients in the Mayo Clinic study);
> Eli Lilly applied for EUA a week or so ago for LY-CoV555, and will apply for EUA in November for the LY-CoV555 with LY-CoV016 combination treatment (both fully tested); both should be available under "compassionate use";
> Regeneron's REGN-COV2 has been in final pre-approval testing for several months; it should be available under "compassionate use".