....why?

People have been asking me questions like, "why are you always happy?", "why do you always smile?" or "why are you always laughing?". My answer is always "cannot ar?" and then i'll start laughing again or I would say "Cause i want to be happy for as long as i can. I mean, it's better to be happy rather than sad right?" I guess that's part of the truth. But it's not the full answer. I realize that only one person knows the full reason why i'm always happy when i'm outside, and i guess it'll stay that way for awhile...