Thumb sucking is a common behavior among infants and young children. It provides comfort and security, helping them self-soothe when they are tired, anxious, or bored. Most children naturally stop thumb sucking on their own by the age of four or five, as they develop other coping mechanisms. While thumb sucking is generally harmless in early childhood, prolonged habits can lead to dental issues, such as misaligned teeth or changes in the shape of the mouth. Parents can encourage children to stop by offering positive reinforcement or distractions, especially as they approach school age and social interactions with peers become more important.