Cod liver oil will help with acne, as much acne and skin bumps are caused by a vitamin A deficiency. It is safe for a baby. Walmart carries an orange flavored one. Mom, you should take some too!!!
For adult acne, Acidophilius works wonders. It can't hurt a baby either, its good for the gut... it coats the GI tract with lots of good bacteria so that bad bacteria, virus, and yeast can't attach to the cell wall.
It could also be a heat rash, especially if it is in an area that is close to wraps (chin, neck.)
If it is very red w/ tiny bumps it can be a yeast rash. (try vinegar)
If you are breastfeeding you should take both the cod liver oil and the acidophilus yourself as well.