[nugator]

I feel the same, the world gets dark if I get too little sleep. But having kids, and the loss of the sleep that means (if you help out in the household and work), did not affect me in the same way. I don't know if I'm chemically programmed to not seeing the world as dark when I have to take care of kids even if I'm really tired or if the kids brighten my world more than the sleep deprivation darkens it.