That's right, Elisabeth didn't want to wear her jewels after Rudolf's dead anymore. She gave a lot of them to her relatives (also to her sister-in-law Marie José in Bavaria), but her daughters Gisela and Marie Valérie as well as her favourite granddaughter Elisabeth Marie got most of them.
As for the little stars: I think I read at the Sisi Museum four weeks ago, that the stars there aren't the original ones, but done by Swarovsky. Once I heard Brigitte Hamann say that the stars are owned by family members. She said something like: "And from time to time I meet young descendants of Elisabeth and they show me one of these famous stars."