My father-in-law read this post detailing my episodes with two bats in my house twenty years apart.
F-I-L: "Let me ask you about the bats. Is there somewhere in your house they are getting in?"
JP: "I would assume so. I'm certainly not letting them in the front door."
F-I-L: "Well, where are they getting in?"
JP: "If I knew that, I would probably have plugged it up twenty years ago, after the first one got in."
F-I-L: "Well, you don't want this to continue, do you?"
JP: "Of course not, but let's think about the whole situation for a minute. My first bat encounter was in the early '90s. I ended up killing the bat. My next bat encounter was last summer and the incident ended with the same result — one dead bat. If these nocturnal vermin visits are on some sort of schedule, I will expect the next one when I am 71 years old. By that time, I won't give a shit if there's a bat in my house and if I call you to tell you there's a bat in my house and — God willing — you're still alive, you — at 95 — will probably have no idea who I am."
F-I-L: "I think dinner's ready."