A-typical Mole watch

My Mom had a great idea! Which is not uncommon for her. G has an A-typical mole on her head. We had it look at by a dermatologist just to make sure it didn't need to be removed. He told us it was fine but to keep an eye on it to see if it changes in anyway. It is not in a place that is visible all the time so I don't always think about it. I don't always remember exactly how it looks and how big it is either. So my Mom suggested I take a picture of it next to a ruler. That way we have a definite color, shape, size to go by and we will know if it changes. She is so smart!