When is a normal time for my baby stop sucking her thumb?

Its highly variable: The age at which children will stop sucking their thumb is variable. Some give it up in the toddler phase and some will continue literally into adulthood. The key is how long does a parent want them to suck their thumb. The problem is that its not just about calming and reassurance. It is a habit that destroys teeth in many kids. Most dentists and pediatricians recommend stopping at 1-2 yrs.

4 years: Even if it persist after 4, if it is an infrequent event don't worry to much, it is usually outgrown. If it is very persistent, then ask your pediatrician for help. You can use reward charts, put on socks if it's before bedtime or during bedtime, replace the thumb sucking with something else (squeeze ball), can also use these terrible tasting (of course non toxic) vegetable nail polishes (otc).

7-9 years: Many children who suck their thumbs did so in utero. It is a hard habit to break, and most children stop on their own between 4-7 years old. The nasty tasting nail polish has not ever worked for me. Socks on the hands may, having a "private signal" when your child id older that alerts him what he is doing and signal to stop can be helpful if your child is wanting help to stop.

Sucking thumb: In addition to destroying teeth prolonged sucking destroys the anatomy of the jaws, especially the upper jaw-this will take a great deal of effort and expense to correct, if possible to correct.