Re: why toe nails fall off
Maybe she's wearing shoes that are too short, or too tight in the toe box? I'm a runner, and I often lose toenails after moutainous 50- and 100-mile runs. I switched to a larger sized shoe, and that has helped a little.
One of my drs. told me that women tend to have toenail problems as they age, as our toenails start to angle up at the tip, causing them to rub on their shoes. He recommended keeping the toenails trimmed very short.
Sorry, no other suggestions.