Well, again, I don't think it is CHILDISH that is the common denominator, or stupid even, but I know that I seem to send signals to others that I am "undefended" perhaps (Psychologically) and that makes me seem younger to them, although what I say and do (except for my odd formulations and metaphores) doesn't seem to puch tose buttons. I suspect some of the smae goes on with man, who have Bipolar that I know, even those who really are older than their years.
Maybe it's the unbridled enthusiasms or deeply felt emotions? anyone? It's not really immaturity.