Glad I read this thread, when getting willow ready yesterday we noticed something under her arm, looked red at first looking closer we seen it was infected, can't believe we hadn't noticed it b4 obv u ladies caught the under arm before it got infected, I felt horrible yesterday, cried all day. I felt like such a bad mum. I know it's just by not drying her properly but now we know. Yesterday was a horrible day took her to the doctor on call which said it was a fungus infection and usually babies get it around the folds at the nappy area but sometimes under their arms.