Vaseline is a petroleum product, an indigestible mineral. What if the baby ingests it, spits it up and inhales it? Couldn't it cause cronic pneumonia since it is unlikely that the body could absorb it? I would be much more comfortable with modified lanolin. Since it is of animal origin, it would probably absorb eventually. If that is not an option (or perhaps if it is), why not have her rub breast milk or colostrum into the nipple? Bonnie