my DD has bad breath too. not really a fishy smell though. she has had it for as long as i can remember and i used to think it was all that breastmilk but since stoppping breastfeeding she still gets stinky breath... also i think it may have something to do with having the dummy in all the time. its worse in the morning. i have been told it can be from infection or sore throat etc but to tell you the truth she gets smelly breath even when she isnt sick. i dont really know waht to do about it either....