Apparently we have rats, mice or possums in the ceiling.
At least Perni has perked up a bit. He had to go to the hospital after midnight on Friday night with a urinary infection. He hasn't been a happy cat since - sleeps all day and complains when he is up. Poor thing. The vet told us today he has a staph infection in the nether regions so no wonder he hasn't been as vivacious as usual. He is on a course of antibiotics at the moment so hopefully that will clear things up.