Smoking is the main culprit for nearly all musicians (I use that term loosely) who prematurely age. My G-d, look at Keith Richards. He looks like he's 100.
Having kids doesnt make your face look older, not at all. But obviously, it spreads the hips, etc, and changes the body to a more motherly figure; but thats part of life.
Keith Richards is the exception that proves the rule. Imagine 40 years ago who would have predicted Richards would still be alive. Not only is he alive but he is still an active and as far as I know healthy man. Remember he fell out of a tree he was climging and hurt himself a few years ago. How many clean living people are climbing trees in their sixities?
He is the kind of guy when you tell your kids drinking, cigarettes and drugs will kill you, the smart alecks will say "what about Keith Richards"