How to ease confusion - mysterious funeral??

I called Dad this morning, and he asked when I was coming to pick him up for the funeral??????? Ummmm.... no one has died. I asked him to remind me who's funeral it was, and he couldn't answer. I didn't want to press too much. I was also hoping he wasn't reliving someone else's funeral (my mother, his mother, my baby brother, etc.) --- Nevertheless, the ALF staff had helped him pick out a suit and he was dressed and fully ready to go. He gets so frustrated / discouraged when he realizes that something's not quite right with his brain. --- I kept trying to divert his attention to our breakfast date in the morning, but he kept asking when I was coming to pick him up. --- He really shouldn't be sitting around in his Sunday best. What should I do? I really wish the staff would have checked with me before going along with what Dad said. I think that made his confusion worse. --- I'm thinking Dad is getting a bit more confused because he's aware of his transfer to another facility. Now I regret asking him to help me pick things he wanted to take along (trying to get him involved). Maybe seeing those clothes triggered something? YIKES!