Welcome to HCM,
After going through history,she is having focal seizure
in this disease it is important to take medicine regularly as there is risk of breakthrough seizure is there, in her case as the is taking Sodium Valproate
200 mg 3 times a day her blood level of drug possibly will not drop to a level that she gets a seizure.I hope there is no breakthrough seizure this time.
Please take that missed dose and continue same treatment regularly 3 rimes a day.
If she is seizure free then discuss with your neurologist
to convert this to sustained release form so that drug can be taken twice a day that will ensure better compliance.
please do not miss the dose .