The Great Dad is an employee of the Springfield Nuclear Power Plant who has a wife, son and daughter.
He attends Mr. Burns picnic, where he pities Homer's sad life. He is hinted not to have such a happy life though, because he and his family are unhappy and looking for therapy at Dr. Monroe's Family Therapy Center. They flee when the Simpsons draw power from the building and later the whole of Springfield.
The Great dad's German voice actor is Peter Musaeus.
