Looping conversations with my dad. Any ideas?

For the past three nights, my dad's conversation has been on one topic (a slightly different on each night) for as long as I would let him talk. One night it was treating people kindly, the next night it was behaving responsibly, last night it was thanking people for their service, i.e. the maid, the cab driver, the wait staff, etc. It went on for an hour each night. If I hadn't excused my self, it would still be going on. I know this is a form of perseveration, and to be expected. But, is there something going on in his head that makes these topics so important to him? He is on the waiting list for a space in a memory unit. I do believe my aunt (who is his care giver, (with lots of hired help and help from my extended family) has talked about his moving in front of him. That's fine. He needs to know what is headed his way. But could this be why I'm getting an endless conversation (more of a professorial lecture) about kindness and compassion?