my cat simba is 4 yo and ever since the day we first brought him home (when he was 2 months old) hes been looking in the mirror and attacking his reflection, chasing things that arent there. he goes to pounce on a bird and when he's about a metre away he just sits down and closes his eyes and relaxes, letting the bird fly away. is there something wrong with him or is he just a bit dumb?