I finally showed Beatrice The Empire Strikes Back and Return of the Jedi. If you've read my book you'll know a little about Beatrice, and about my anxiety that she not be exposed to the World's Biggest Spoiler. Despite the odds (which worsened considerably after her cousin Rory learned about Darth Vader without ever having seen ESB), I somehow managed to keep the secret from her and her brother Zachary. But I felt I was pushing my luck. Now was the time for the big reveal.
Once "I am your father" is out of the bag, there's no reason not to go on and see ROTJ. We watched it together a week later. Above is a video of Beatrice's thoughts on the two films.