Febrile Seizure Recurrence: Given the boy's history of previous episodes of provoked seizures from fever, the most likely diagnosis is a recurrence of febrile seizures. Febrile seizures are common in children and often recur with subsequent febrile illnesses.

Viral Meningitis or Encephalitis: Although less common, viral infections affecting the central nervous system can cause seizures and fever. The history of previous febrile seizures does not rule out the possibility of a more serious infection.
Bacterial Meningitis: While less likely than viral causes, bacterial meningitis is a significant concern in any child presenting with seizures and fever, as it requires prompt antibiotic treatment.

Central Nervous System (CNS) Infection (e.g., Abscess, Empyema): Infections within the CNS can present with seizures and fever. Missing these diagnoses could lead to severe consequences, including increased intracranial pressure, brain damage, or death.
Intracranial Hemorrhage: Although rare, an intracranial hemorrhage could present with seizures and fever, especially if there is an underlying vascular malformation or trauma.
Meningoencephalitis due to Other Pathogens (e.g., Fungal, Parasitic): In immunocompromised children or those with specific exposures, less common pathogens could be responsible for the symptoms.

Autoimmune Encephalitis: A rare condition where the immune system attacks the brain, potentially causing seizures, fever, and other neurological symptoms.
Mitochondrial Disorders: Certain mitochondrial disorders can increase the susceptibility to seizures, particularly during febrile episodes, due to impaired energy production within neurons.
Genetic Epilepsy Syndromes: Some genetic conditions predispose children to epilepsy, which could be triggered by fever. While rare, these conditions are important to consider, especially if there is a family history of epilepsy or developmental delays.