It almost sounds like she may have some sort of intestinal bug going on--and that could be causing the fecal incontinence.
I think I would at least bring a fecal sample in for analysis, even if it's not with your regular vet, and see if it turns up anything. Might be a simple metronidazole fix.
"We are--each of us--dying; it's how we live in the meantime that makes the difference."
"It's not what you gather, but what you scatter that tells what kind of life you have lived!"
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