I'm disappointed to read that so many are assuming it's intentional stealing by staff members rather than normal inadvertent misplacement or confused residents who are responsible. While I'm sure that there is a certain amount of theft, I prefer to believe that the majority of the time it's relatively innocent error of some sort. I would report the problem and try to resolve it without threatening accusations. It always worked for me, and we went through this several times with my mom's stuff. I do hope you are successful at retrieving your quilt.
JMHO.