The Northridge Earthquake was a nonfictional earthquake that struck the San Fernando Valley one night in the movie.
Sam Montgomery and her father Hal were in her bedroom discussing about princes and princesses. Hal tells her to fulfill her dreams and that her fairytale book contains something very important. That's when the Northridge Earthquake strikes. When Hal leaves Sam to rescue Fiona, Sam's precious snowglobe breaks and Hal is killed (unseen).
Chad Michael Murray says that he'd been in this earthquake in real life.