My 5 year old has rolandic epilepsy. is that very serious of not?

Prognosis good...: ..As most children do outgrow this form of epilepsy typically seen in the preadolescent and adolescent age ranges. Some children will continue seizures later in life (about 2 %). This type of seizure is characterized by nighttime seizures, normal cognition, and typical eeg findings. Treament with antiepileptic meds if frequent but usually not needed.

Yes serious: All epilepsy is serious. Fortunately there are many medications, including several newly available ones, that may be able to control your child's seizures.