My 4 year old daughter got a wart on the bottom of her left foot,and we were wondering what may have caused this. It is on the "pad" of her foot in middle. I was guessing dirty sandals without wearing socks?.

It is a virus that enters the body through a break in the skin. The virus grows in warm, moist environments. It grows in warm, moist environments, such as shoes when your feet perspire and the moisture is trapped.
I make a mixture of garlic and olive oil and apply it to the wart and
Keep applying it regularly until it disappears. It didn't work a couple times for me but I think it was because I didn't keep up with it.