The main causes for children cry include the following areas: 1. neonatal dacryocystitis. It is the most common cause of children's tears, about 5~6 neonatal morbidity, and often is unilateral. 2. Neonatal logadoblennorrhea. This is a super caused by acute bacterial conjunctivitis, and often attack 2~4 days after the birth. 3. Trichiasis in congenital eyelid, which is more often to see. This happened in children with blink at the same time and rubbing eyes with hands. 4. Congenital lacrimal point and lacrimal canal lock, or no tear town. 5. Other reasons, such as conjunctivitis, inflammation of lacrimal gland can also cause the watery eyes.