Question: The Griswold family's vacation misadventures feature in both "Hotel Hell Vacation" and the "National Lampoon Vacation" series, as sanctioned by what company?
Sentence (from "Hotel Hell Vacation"): Although sanctioned by Warner Bros. (which holds the underlying rights to the "Vacation" series characters and concepts), this film was not sponsored by National Lampoon, Inc., which initiated the "Vacation" series.
Relevant evidence: Yes