Hi Shelley,
I'm so sorry to hear about DD. Unfortunately, I did have a plantar wart about two years ago. I think I got it from the locker room at the gym. I bet DD got it at school, maybe in gym class. As you probably know, it is actually caused by a virus that you pick up through any cracks on your feet. That's why it's key never to walk barefoot around pools, public showers....etc. Sorry, I digressed there a bit.
I tried some treatments that the pharmacy had to offer but it was taking so long to get rid of, I finally went to see a podiatrist. Since I'm on my feet all day, it was very painful. The plantar wart itself was much more painful than the treatment though.
I would honestly suggest taking DD to a podiatrist. I think that would be the most effective way to treat her. They hurt like heck and they are so nasty and stubborn to get rid of!!!
The podiatrist will scrape and then use a freezing treatment on it.
Hope she feels better soon!!!