Teething is a normal stage in an infant’s first years. It often starts around 4–8 months and can continue until about 30–36 months. The lower front tooth usually appears first and the last molars come in near age three. Many parents notice irritability, gum swelling, drooling, sleep disruption, mild fever, fussiness with eating, and extra chewing. Around six months, maternal antibodies decline, so minor infections can mimic teething signs. That overlap makes knowing when to call the pediatrician important. Primary teeth matter beyond a smile. They help with chewing, speech, facial shape, and hold space for permanent teeth. Good daily routines and early dental visits lower the chance of cavities, infection, or misalignment later on. This article sets clear expectations