"Puberty screwed up levels of gauging whether his drugs were working or not. He was having more seizures," Grunberg tells PEOPLE. "Hundreds a day."
Luckily for Jake and his family, the 12-year-old was eligible for a brain surgery that turned out to be life-altering. "They removed the part of the brain that has the most epilepsy activity," Grunberg says of his son's operation. "Now Jake is only having a little tiny episode once every three weeks."
"To me," the proud father says, "that's a home run. We never thought that was possible."
With Jake's health improved, Grunberg has turned his attention to developing www.talkaboutit.org, a Web site that raises awareness about epilepsy, and has a social networking component for visitors.
"When we first discovered Jake had epilepsy, we went online, and all you discover is horror stories. Talkaboutit.org is a place where you can get information, and you don't feel alone," he explains.
Greg's All-Star FriendsGrunberg enlisted famous pals like John Mayer and Jennifer Garner to participate in the Web site – and jokes that he's turned into 'the paparazzi of Talkaboutit.org.'
When Grunberg spotted Jack Black in a parking lot, he says, "I said to the valet guy, 'Is that Jack Black?' I got my camera out and I was like, 'Jack!!' " The actor taped a statement on camera for Grunberg's site on the spot. "I take my camera everywhere," Grunberg says. "I don't take 'no' from anybody."
When he's not working on his Web site, Grunberg says he's enjoying Heroes' third season. "My character [Matt] is now getting the family he's always wanted. But he has to protect that family at all costs," says the actor.
In some ways, it's not unlike his own family life, Grunberg says. "It's a very personable and relatable storyline."
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