RE: How old should the little guy be?
My son was 2 years old when he started goin to the stand. In fact, he was in the stand with my wife and I when she killed her first deer. He is 6 now and he still remembers the whole thing, seeing the deer, waiting FOREVER for mom to pull the freakin trigger, waiting after the shot, getting down and following the blood trail.
Go ahead and take your kids to the stand sometimes. You never know when you'll get lucky and make awesome memories.