my 6 mth old developed a rash on her chin, neck and chest and i can't get it to go away. i keep it dry, air it as much as possible considering all the slobber. i tried lotrimin for yeast(my oldest had yeast in her neck at that age), and lanolin to protect it. she scratches it so i can see it's itchy. it's red and rough/dry feeling on her chest and chin(those are patches), and is spreading into red bumps across all her neck rolls. she only has breastmilk and some veggies and oatmeal with no additives, but my diet is awful. any ideas?