Presumably because Anthony Michael Hall and Ethan Embry were too busy, Ed Helms is in discussions to play the role of an adult Rusty Griswold who sets out to take his own family on a shenanigan-filled vacation. The film was written and will be directed by Jonathan Goldstein and John Francis Daley (Sam Weir, himself!) No word if Clark is involved in the trip but you know Chevy Chase is going to love playing a grandfather. (Yes, I am being sarcastic. He will hate it.)