Judith Barsi, who did the voice for Ducky, was murdered by her father four months before the film's release. Judith was only ten years old. Her headstone includes her famous line in this film, "Yep! Yep! Yep!"
Throughout production, the film underwent severe cutting and editing of footage. Steven Spielberg and George Lucas thought that some scenes in the movie would appear too dark and intense for young children. Spielberg told Don Bluth while looking at the scenes from the film, "It's too scary. We'll have kids crying in the lobby and many angry parents. You don't want that." About nineteen scenes comprising ten minutes of footage, mostly pertaining to the Tyrannosaurus Rex and the five characters in mild peril or distress, were cut or trimmed. Bluth was unhappy with the cuts and fought to keep the footage, but felt like he had to do so, making this film only 69 minutes, one of his shortest. He claims to have a personal copy of the film reel with the whole thing, though no word on whether or not it will ever see the light of day.
Old Rooter didn't appear in the original script but was added to soften the blow of the death of Littlefoot's mother.