What the Docs May Do
Your pediatrician will likely reassure you regardless of whether your child is the biter or the biting victim—this just isn't a behavioral catastrophe, although it may feel like one! Toddlers with developmental delays, especially expressive language delays, are more likely to act out physically in my experience. This should be considered when assessing the situation.
The biting child who is aiming his teeth at his parents should be ignored, as much as possible. I gave this advice for many years before my first toddler bit me one night. No reason, just out of the blue during reading time. As I let out a yelp, my advice of "ignoring it" came flooding back to me through my tearing eyes. Your best attempt to distract and redirect is still the mainstay of advice. If ignored, the behavior will gradually disappear or "extinguish" as the behavior experts like to term it.
The biting child who is recurrently sinking his teeth into little Rebecca in playgroup needs to be handled a little more delicately. Although removing the biter from the situation is advised, raising of voices, slapping or biting the child back, or other punitive approaches (called negative reinforcement) can actually reinforce the behavior.
I also tell parents that a daycare provider who is stumped or surprised by biting behavior worries me a bit. This is such a ubiquitous behavioral issue that almost all experienced daycare providers of this age group have handled it many times over.
More 15th Month Health Help
Even the most confident parent has concerns about her child's health and wellness from time to time. (If you have any pressing concerns or questions about your baby's health, please check with her healthcare provider.)