Truman makes the oddest chirping noise when he spots a laser dot on the floor. I haven’t heard cats make this noise other than when they see birds outside and they’re inside. But Truman chirps and chirps and chirps as he gallops around chasing the laser pointer.
I decided to look this up and researchers believe cats make this noise when they’re trying to hunt something they can’t physically get at, like when a bird is sitting on a branch outside and the cat is stuck inside. Truman doesn’t see anything physical associated with the red dot on the floor, other than the dot itself, and therefore he apparently starts chirping trying to attract its attention.
One of these days he’ll get this dot.