My bby had d same issue @ a month old. She's jst 6weeks now. Wat i did was 2 see my pediatrician cos after birth she had cold(Sneezing & thick catarrh) & rashes.Some rashes disappearz on their own depending on d kind of rash.If its d one wit white pulse in it, den u av 2 see a pediatrician. After which i backed it up wit agnesia powder. Its d best wen it comes 2 rash. For the cold,i was applying silver bed on d top part of her head & menthol(applyin on her chest), then for now, dnt expose her.