Children with fever giggling for no reason, mostly due to high fever caused by temporary disorders of brain nerve function, there may be sequelae. If the child’s general condition is good, no special discomfort, can be closely observed, generally no sequelae. If there is a call, eyes upturned, limbs stiff, lips and lips, suggesting that the fever convulsions, or even encephalitis, may leave epilepsy, as well as intelligence, hearing, movement disorders and other sequelae. 1. febrile convulsions: children’s thermoregulatory function is still imperfect, high fever may cause temporary abnormal brain discharge, giggling, eyes upturned, limbs stiff and other manifestations. The majority of febrile convulsions have a good cognitive prognosis. Even in children with complex febrile convulsions, there is no significant difference in long-term cognitive function and behavior compared to children of the same age. However, a small percentage of children with febrile convulsions who have risk factors may develop epilepsy. 2. Encephalitis: Bacteria, viruses and other pathogens infect the brain, encephalitis, meningitis, may cause transient giggling, or even poor response, not responding to calls, gibberish, vomiting, headache, etc., such as brain parenchymal damage is serious, there may be intellectual disability, hearing impairment, motor impairment and other sequelae. When a child develops a fever and giggles for no reason, he or she needs to be seen by a specialist for evaluation and treatment.