KCNQ2 and genetic developmental and epileptic encephalopathy: However, it was notable that the electroencephalogram in patient 2 showed persistent burst‐suppression patterns even beyond 3 years of age, which has not so far been described in cases of early infantile epileptic encephalopathy caused by KCNQ2 or SCN2A mutations.23 Further investigations in a larger cohort of patients are warranted to explore characteristic electroencephalographic progression and optimal antiepileptic strategies for patients with NSF‐related early infantile epileptic encephalopathy.