THE LAST 4 OR 5 NIGHTS, MY 9 MONTH OLD BOY HAS STARTED BEING A LITTLE SICK EVERY MORNING APPROX 5 OR 6AM. IT'S JUST A LITTLE BIT AND HE DOESN'T DO IT DURING THE DAYTIME. HE DOES GO DOWNSTAIRS FOR A DRINK
OF WATER, COULD IT BE AN AIR POCKET CAUSING HIM TO THROW UP.
HE IS ABSOLUTELY FINE IN EVERY OTHER RESPECT.

My guess is that he could be hungry. Our youngsters do it if left overnight too long without food.

I agree with Herbiedax, an empty stomach can cause this. Try giving a biscuit or something light at bedtime.

Could be numerous things, what breed is he?

IF it's that yellow bile stuff, definitely try giving him a treat or a couple of doggie biscuits just before bedtime. My shar-pei used to do it until I started giving them a bedtime snack.

Splitting the daily meal into two can also help alleviate this problem.