Tenant sees a ghost. What should my response be?

[John Park]

So...one of my tenants is claiming that she and her daughter are seeing a spirit in the house. Did not know how to respond to this. If it was a maintenance item I would send my guy to take a look right away, but what the heck I am I supposed to tell someone who's seeing things? BTW I don't believe in ghosts (although those who do believe in ghosts are free to do so and disagree accordingly), but I don't want to be politically ghost believer insensitive and tell her she's crazy. Any advice would be helpful, Ghostbusters, new or old, need not apply.