Some cats do not "mature" enough to act as an "adult" cat until they are at least 5 years old. It appears that Cubby is one of those. I am believing that you are dealing with a specific personality of a cat, and not so much one of being immature. Be happy that you have such a furkid, because there is plenty of time for him to be more calm and serious and to conduct himself as a "mature cat". My Chrissie will be (I believe) 3 years old this year, although there are no birth records on him, he is my 13 lb kitten! He still plays chase-and-ambush, and bats cat toys around on the floor. Of all of my furkids, he is my special one.

........wayne