Newborns suck their thumbs as part of the suckle (sucking) reflex. If a baby cannot suck, it cannot get nourishment and without medical intervention, the baby would die. As a newborn ages, a baby sucks because hand-mouth exploration is one of the primary ways babies explore their world and learn. Babies may even try to suck their toes! As babies learn to scoot, then crawl, then stand and walk, they ignore their toes for sucking but still return to their thumb when hungry, tired, frustrated, or need self-comforting. Now, they don't need the suckle-reflex but sucking the thumb lingers because it is comforting. By 2-3 years old, toddlers typically stop sucking their thumbs, but many still do until pre-pre-school at age 4. Still many 4-year olds return to the thumb when very stressed. Children who persist in thumb-sucking may need adults to help them to stop. However, many kids still periodically suck a thumb once in a while even up to age 8-9 years old. But by then, kids realize their friends will make fun of them. Between social milestones and peer pressure along with parental guidance, most kids stop thumb-sucking without problem before age 4. If you are in grade school and still suck your thumb sometimes, try putting a band-aid around the thumb as a reminder to stop. Kids who suck thumbs beyond age 4 can mess up the alignment of their teeth, pushing the top teeth forward like Bugs Bunny. This often requires braces later to correct tooth alignment. So whatever you can do now to stop will help you in the long run.

It's always up to the person as to what they want to do about their thumb sucking habit. Except for its possible social definition, which seems to be changing slowly because of its exposure on the Internet as more common than previously thought, the many benefits may outweigh any other issues (legal, free, convenient, without calories or drugs, instantly calming, aids concentration and sleep, non-intrusive, quiet, etc.).

Females suck their thumb more than males, especially in the older age groupings, by about a ratio of 3:1 while as the age reduces so does this ratio.

Babies mostly do

With the advent of the Internet the subject of adult thumb sucking has left the shadows and, as a result, it is now well known that adults do, indeed, suck their thumb. The best estimate, so far, is that affects about 2% of the adult population in the United States.

tell them a story about a kid you used to know that sucked their thub and one day it turned purple then it droped off.

they'll stop straight away if you tell them it's true and they believe you

Depending on your age and the health of your dental structures, the best way is to make sure the intensity, duration and frequency is high (usually 6 or more hours each day). It also helps to exert reasonable pressure on the upper incisors. Note, though, that the older you are and the healthier are your dental structures, the less likely it will create an "overbite", or more correctly, an overjet.

They CAN suck their thumb, however by that age, they should have grown out of it.

Get him to suck something else...

No.

No. But don't suck on your thumb, it's weird.

Gently remove her thumb and replace it with a pacifier. In the long run, when it is time to break the habit, you can take away the pacifier and make a clean break. Thumb sucking is much more difficult because it is always with them. When they go to bed at night, it is right there. Pacifiers also tend to be more hygienic.

Yes she does, check online they is one pic showing her doing it.

Thumb sucking at age 11 is indulged in by about 10% of those that age with the ratio of female to male being about 2:1. As such it's "normal" and, in fact, can be found in about 2% of the adult population of the United States.

operant conditioning

they are exploring and still learning how to use there mouth muscles to chew bigger things so they suck there thumb to start.

The gender ratio is approximately 3:1 favoring females. As to why, it's more socially acceptable for a female than it is for a male due, typically, to societal stereotypes woven over the concept that thumb sucking depicts a type of vulnerability, something that males typically don't favor as an image.

Neosporin and if u don't want her sucking on it put gloves on her hands