According to The Bump, stopping toddlers from spitting involves looking for patterns in the behavior, trying to understand why the child is spitting and reinforcing positive behavior. Because spitting is sometimes a sign of anger, it is important to respond to the underlying emotion, separating it from the actual behavior.
Watching toddlers when they spit helps to make clear the reason for the spitting. Sometimes toddlers spit to get attention, others spit when they're angry and still others spit because they find it interesting. Toddlers cannot adequately voice their feelings, so they sometimes act out through hitting, biting or spitting.
Instead of punishing toddlers for spitting, parents should reinforce positive behavior. A child that receives attention for spitting may repeat the activity just to get more attention. Timeouts can be given for spitting, but the best tactic is to praise the toddler for good behavior. Parents should try to find the root cause of the spitting and discuss it in simple terms with the toddler. This helps him find other more constructive ways to deal with anger.
Toddlers often spit for the same reasons they hit or bite, but spitting is less damaging physically. Toddlers do not understand the concept of contempt that some adults associate with spitting, so parents should not respond to them as if they have adult emotions and reactions.