Thumb sucking between the ages of two and four is not very worrying. Most children give up the habit when they find other, more interesting activities to do with their hands. However, some children continue to thumb sucking after they are six years old. This is where the problem starts. Do many parents think of how to stop thumb sucking?
At this age, habits are well established and do not give up easily. On the other hand, it causes many facial deformities as permanent teeth grow out. The child may experience an open bite where a large gap is visible between the upper and lower front teeth. It is very unaesthetic and difficult to fix even with orthodontic treatment.
Sometimes children rebel when their favourite activity isn't done. It's important not to judge them. The habit will not disappear for a moment. It will take some time. Patient. It also shows your child that you believe in them. This is very helpful in building a child's trust.
Don't worry if the habit lasts until the age of four. No permanent damage was caused. Keep encouraging the child, but express your opinion that thumb sucking is absolutely undesirable.
Don't take an authoritarian position, but defend yours. Your child knows and understands a lot without realizing it. They are constantly watching you for clues. Give them positive vibes and they will pick up on it sooner than you think.