I have a zero tolerance for a thieving nurse/cna. If someone is stealing, reagardless of supplies or meds, that person needs to be replaced. Trying to talk to them or any other staff does not work, because everyone denies it, or denies knowing about it. A few may share a concern about missing supplies or meds, but for the most part, that is far and few between, because the other nurses do not want to "snitch". (from my experience).
Any agency who does not replace a nurse via request and tries to impose unwanted staff on you is simply all about the money. Bottom line. And anyone who has that mindset, doesn't really care at all about the person you care about.
If you know who it is, replace that person ASAP. Been there. Done that.