“National Lampoon’s Christmas Vacation” begins with the Griswolds buying their tree to bring home, just in time for a family holiday. With no goodies left to buy, Clark decides to cut down a huge tree from the forest. However, this tree happens to be home to a squirrel. The bush-tailed rodent makes its presence known by leaping from the tree to terrorize the various members of the family, before being chased away by the dog. However, on the day the scene was shot, the cast and crew arrive to discover that the trained squirrel has died.
During an interview with Rolling Stone, director Jeremiah S. Chechik explained how what was supposed to be a simple day of filming turned into anything but ordinary. “For the dog and squirrel chase, we hired an animal trainer who trained them every day for several months to run on the set,” Chechik recalled, going on to say that plans for the scene went out the window when the squirrel died unexpectedly. “I got out of my car and saw everyone standing in a huddle shaking their heads and I knew something was very wrong.”.”
The cast and crew had to move on, now using an untrained squirrel. Diane Ladd, who played Clark’s mother, explained why her frightened look during that scene was so real, as the squirrel Wrangler tells her, “If someone screams or scares someone, their claws are like razor blades.”