Due to incomplete seizure control at six months of age, whole-exome sequencing revealed a heterozygous deletion in exon 8 of the SCN1A gene (ENST00000674923.1), identified as c.606del (p.Tyr202Ter), associated with developmental and epileptic encephalopathy-6B (OMIM#619317), Dravet syndrome (OMIM#619317), and generalized epilepsy with febrile seizures plus, type 2 (OMIM#619317)/familial febrile seizures-3A (OMIM#619317). This evidence concerns the gene SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy.