Nancy,
How is your sister doing now? I hope she is doing a little better now?
I'm sorry you didn't get any reply here from someone who has gone through the same thing. I haven't read anyone having this before. My Dr mentioned it to me when I was struggling with constipation brought on by pain meds. Once I stopped the pain meds thing went back to normal. Although during treatment I had to use stool softeners, strong laxatives and the occasional enema to keep things moving.
Stay Strong
Tim