Final answer:
Fever is the most common cause of seizures in children, often causing febrile seizures, while epilepsy is a less common cause, characterized by recurrent seizures due to abnormal brain activity.
Step-by-step explanation:
The most common cause of seizures in children is fever. Febrile seizures, which are seizures that are associated with a high body temperature but without any underlying health issue such as an infection, are relatively common in young children. These seizures can be alarming to witness, but they are usually harmless and children typically outgrow them by the time they reach school age.
While epilepsy is a disease that is characterized by recurrent seizures and is caused by abnormal electrical activity in the brain, it is less common as the cause of seizures in children when compared to fever. Infection, brain injury, or a tumor can be potential underlying causes for epilepsy, and the condition can sometimes be managed with medication or, in severe cases, surgery.