Betty White IAMA on Reddit: http://www.reddit.com/r/IAmA/comment...tty_white_ama/
It's making me oddly teary:
Question: What has been your fondest memory working with Bea, Rue, and Estelle on the show?
Betty: Just being with all of the girls was wonderful. Rue and I had such a ball because we would play games when we weren't on the show. We used to have riddles for each other between scenes and when the scene was over we would give each other the answer.