Thumb sucking

Thumb sucking is a behavior found in humans, chimpanzees, captive ring-tailed lemurs, and other primates. It usually involves placing the thumb into the mouth and rhythmically repeating sucking contact for a prolonged duration. It can also be accomplished with any organ within reach and is considered to be soothing and therapeutic for the person. As a child develops the habit, it will usually develop a


Thumb sucking is a behavior found in humans, chimpanzees, captive ring-tailed lemurs, and other primates. It usually involves placing the thumb into the mouth and rhythmically repeating sucking contact for a prolonged duration. It can also be accomplished with any organ within reach and is considered to be soothing and therapeutic for the person. As a child develops the habit, it will usually develop a "favorite" finger to suck on.
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