Thumb-sucking is a totally normal toddler habit, but at some point your child does need to give it up. Most dentists agree that thumb-sucking should stop by age 4 (the same time kids should also give up the pacifier), since after that it can interfere with the development of a child's teeth and palate. Of course, ending a thumb-sucking habit is much harder than weaning from a pacifier, since you can't simply take your toddler's thumb away. Ideally your child will stop on his own, but if he does need a little extra help, here's how to make the transition smoother:
• Stay positive. Focus on praising your child when he doesn't have his hands in his mouth instead of criticizing him when he does. Reward your child for not sucking his thumb for a set amount of time (start with short stretches like in church or during a movie).
• Limit when and where your child can suck his thumb. Start by saying he can only suck at home. A week later say he can only do it in bed at night. When he breaks these rules, remind him lovingly and don't embarrass him.
• If your child expresses a desire to stop but is having trouble, there are ointments available that will make his thumb taste terrible. Remember though, these only work if the child is on board -- a child determined to suck his thumb will go right on doing it in spite of the nasty taste.