Typically, babies will suck the thumb or a portion of the hand, which is perfectly normal. Often when hungry and waiting to be fed, you will see babies trying to get the hand into the mouth. Even as babies grow into younger children around the age of six, you may still see some thumb sucking, which is somewhat like a security blanket. However, most babies will give this up on his/her own but if not, you can do a few things to break the habit.
For little babies, you could use a pacifier in place of the thumb. Most often, the baby will only suck on the pacifier until relaxed or asleep. As the baby grows older, the need for a pacifier will stop. Now, the other thing for babies is to make sure your baby is being fed enough. While not overly common, some babies are simply not being fed enough so increasing food intake can help.
As your baby reaches age one to one and a half, the thumb sucking could be from sheer boredom. Remember, babies need stimulation, playtime, toys, etc. If a baby is not active enough, he or she could turn to thumb sucking to relieve tension and/or frustration. If you notice your child sucking on the thumb or hand more and more often, start changing up the schedule to incorporate more time of activity.
If your baby were teething, he or she may find thumb sucking helps calm while also reduce pain. In this case, the thumb sucking is not going to hurt but to help, again look for a quality pacifier along with teething rings to distract the child from the hand to other objects that can help. Most often, when the teeth come in, the thumb sucking will begin to diminish.
Sometimes, you will have an older baby or child that sucks his or her thumb because of stress-related issues. I remember when my son was four months of age. He was never much of a thumb sucker but after changing babysitters, I found this habit returning. At first, I did not give it much thought but then it dawned on me that other behaviors had changed as well.
To make a long story short, I showed up at the babysitter’s house early and unannounced one day only to have my heart drop. She was nowhere in sight, instead her 12-year-old son was watching 11 kids. There was my son, on the floor in a dirty diaper with older children jumping over him. You can only imagine the horror I felt. Although I was a young mother, I knew this was very wrong. Once I found a wonderful daycare provider for him, the thumb sucking stopped. While this habit is not always associated with something bad, just pay attention.