Charlie worshipped Dan.
Dan was cooler than his dad, and he understood things, and he never treated Charlie like a kid. He was smart, and funny, and (at least around Charlie) he always seemed to know the right thing to say.
So no one was really surprised when Charlie came home for Thanksgiving freshman year of college with his friend Matt, who was smart and funny, and had brown hair and a nose that was just a little too big for his face.
"Charlie's bringing a friend," Lisa warned Casey on the answering machine.
He and Dan shared a smile.