We noticed our 10 month old grandaughter has a boil on her back side a couple days ago and took her to the Dr. The Dr perscribed antibiotic and the nasal cream. The boil started to get a little white head on it last night, but this morning, the head was gone. The spot feels a little harder and has started to turn purple. Can you tell us why it is turning puple? Is it healing or getting worse? and can we use Ichthammol to draw it out?