It’s common for children to suck their thumb at a young age. Drs. Luis Leite and Rick Singh and our team want you to understand the potential issues that can surface down the road if the habit isn’t broken early on. It’s normal for infants to explore the function of their mouths by putting objects like their thumbs inside it. You shouldn’t be concerned if your baby regularly sucks his or her thumb. For infants who are still growing their baby teeth, thumb sucking can help with stimulating growth and development of their baby teeth.