FHM. There are few neurological phenomena that are as perplexing as CACNA1A-related hemiplegic migraines. Neither migraines, seizures, nor strokes, CACNA1A-related hemiplegic migraines are poorly characterized neurological events that often defy explanation. In a recent publication, we characterized how hemiplegic migraines in children with CACNA1A-related disorders present across time. Here is what we found.