"Normal" gifted sleep is a hard thing to judge... DS~7 has been trending downwards in sleep, right now it is 9 hours. I was closer to 7.5 hours when I was 8 and was down to 5 by high school, but it was a steady trend.
Both DS and myself, suffer the "brain won't shut off" for sleep. He needs music, I tend to have a documentary on. Reading doesn't work for me as it just gets the brain reengaged. If it is his brain won't shut-down, maybe some way for him to focus his attention away from his thoughts like music would help.
The number one way we gauge if DS is "getting enough sleep" is whether he wakes up on his own in the morning.
