My 17 months old son, is currently growing one of the molars, yesterday we started noticing bad odor coming from his mouth. today, the smell is still there. he brushes his teeth quite regularly. could you please advise if this is normal?

Usually infection: Bad breath in toddlers is usually caused by a cold or allergies. The excess mucus can cause overgrowth of bacteria in your babies mouth. Additional infections include Sinus problems, foreign body, swollen tonsils, and tooth decay. Even with regular brushing many of these can occur. See your pediatrician so they can do a thorough exam and determine/treat the underlying cause.

Bad breath: 17 month old does not have the eye-hand coordination to properly brush. Additionally, brushing alone only gets teeth about 65% clean. He needs to be flossed daily, and you need to help him brush properly. He's 5 months past due for 1st Dental Exam...see a Pediatric Dental Specialist, a Pedodontist. if there is no dental cause, then see Pediatric Medical Specialist, Pediatrician.