Hello Grama4B.
First rule is to Learn Proper seizure 1st Aid. It's really quite simple.
http://www.epilepsy-info.com/html/response.html Next is have his Parents start a Journal or Seizure Diary. You can locate an online tracker at Epilepsy.com or you can write everything down. Under Tips is a Post from Meetz, about everything that should be included. This is most important when starting a new medication/dose.
As for his behavior, the Journal will show a pattern if anything is out of sorts or different than normal behavior. Keep in mind, Everyone experiences their med in different ways. What works for one may not work for another. But, a Good diet Should help his meds work properly w/ the fewest side effects. Also, Please do some homework about the Ketogenic Diet & ask his parents to consider it, B4 deciding on another med to try. If Keppra does not work for him. Whether it's continued Seizures or intolerable side effects. .
Phylis has an excellent article on her site for parents of newly diagnosed children. www.epilepsytalk.com. Please visit & read the article. You don't have to join to read her info.

She visits us on a regular basis if you have questions, too.
If his parents have problems getting him to take his medication, I have recommended, in the past, that meds be inserted in a Small 'shot cup' of Jello.

Ever hear of 'Jello Shooters'?

Pudding can be used, too.

Same w/ Applesauce. Just a Tsp. should do the trick there. Just don't let him watch when the pill is placed in these foods.
Do you know what kind of seizures your grandson has? The epilepsyfoundaion.org has a description of most seizure Types. Also, chek out the Recommended Books for All Ages. My opinion: Everyone needs to be educated, including children. Our Resources has links to most of these sites & more Info.

Best Advice: All sites agree. Continue to treat the child as 'normal'. It will take Time, Patience & support from friends & family. But, he will adjust. And so will they. The best news: Children of his age Usually outgrow seizures.

Keep your fingers crossed. Any more questions or just wanna talk some more, I will be here for you. HUGS!
Love Candi