BECTS (Benign epilepsy with centro-temporal spikes) is the most common, presumably genetic, type of focal epilepsy in children. It can develop in various ways, leading to mild or severe neuropsychological deficits, including linguistic, cognitive, and behavioral impairment. We describe a eleven year old male child with epilepsy with continuous spikes and waves during sleep (CSWS). His behavioral disorder, characterized by hyperactivity, impulsiveness, attention deficit, and aggressiveness, became progressively evident a few months after epilepsy onset, suggesting a link with the interictal epileptic activity characterizing CSWS.