The Frighteners
Jackson's eldest son, Billy (born 1995), has made cameo appearances in almost every one of his father's films since his birth, namely "The Frighteners", "The Lord of the Rings" film trilogy, "King Kong", "The Lovely Bones", and the third film of "The Hobbit" trilogy. His daughter, Katie (born 1996), appears in all the above films except "The Frighteners". And partner Fran Walsh makes a short cameo in "The Frighteners" as a woman walking next to Cyrus and Stuar just prior the scene featuring their son Billy.