My dad was in rehab for six months with a really bad UTI. While there he suffered from hallucinations and delusional thinking. He's been back home since July; since the UTI has cleared up he is mobile again and rational most of the time. Some of his delusions have persisted, but these are mostly easy to deal with. There is one, however, that's got me stumped. He thinks that while he was away, a lady who works at the rehab facility and her son somehow broke into our house and stole various things, including all his musical instruments. I cannot argue with him rationally about this: even though all his instruments are still here he still insists that they had been stolen and somehow were returned. Plus he's made a list of other things that were "stolen," most of which we had never owned in the first place. When I ask him how this all could have happened without my knowing it, as I live here too, he says that the two got in through a secret doorway in the back of our (second story) condominium. He even claims he saw a press conference about it on the national news, and that he's been in touch with the FBI.Lately, when he starts talking about this I try to change the subject, but the part that I don't know what to do about is that he has called the local police twice since he's been home to report the "theft." The first time I kind of freaked out when I opened the door and saw a policeman there. I spoke to him privately and explained the situation and he was very understanding. I told my dad that the police were working on the case and would be getting back to him. This seemed to satisfy him for a while, but then, about two months later, I opened the door to find the sheriff waiting outside! He had called her. I tried to find a way to get the sheriff alone to explain things to her, but my dad went on a long ramble, accusing the woman at the rehab of committing grand theft, etc. I tried to gesture to the sheriff that this was all in my dad's head and I think she understood. After this I told my dad that I was in daily contact with the sheriff and they were working on his case. But yesterday he started demanding that I get the sheriff's number for him so he can call them again to renew his report. I try to use the tactic of changing the subject, assuring him that the sheriff told me that they were working on the case, but it's not working. He's constantly asking me to get him the phone number for the sheriff. I don't want him to keep calling the police about this "theft" that never happened. I hate to waste the police's time, I don't want the woman at the rehab facility to be accused of anything which I know she didn't do, and I'm afraid that if he calls too often, the state might force me to put him in a facility. How do I deal with this without making my dad feel that I think he's "crazy"?