CDKL5 and epilepsy: Bahi‐Buisson et al. have described a three‐step epilepsy phenotype associated with CDKL5 mutations in 13 girls aged from 2.5 to 19 years: early epilepsy (stage I), then epileptic encephalopathy (stage II) and finally, late multifocal and myoclonic epilepsy (stage III).