DS is 8 months old and goes to bed at 7pm every night. He wakes up once for a bottle and diaper change between 4am - 5:30am and most of the time goes back down for another 30 minutes to an hour afterwards.

There are a couple of issues I have with this. First, the obvious one is that DH and I have been extremely sleep deprived. We both work full time and it's impossible to get back to sleep after getting up at that time of the morning. Second, I know DS is sleep deprived as well. He is always extremely tired and fussy in the morning, for the longest time I just thought it was normal, but the other morning he "slept in" until 7:30am and was extremely happy and energetic. It was like we had a totally different baby, he's never been like that in the morning before. And finally, a few months ago our pediatrician said that he should be sleeping 12 hours straight and if he isn't that we should leave him (assuming nothing is wrong) so that he learns to sleep this long.

On the flipside, DS has been sick 5 times in the past 3 months (since starting daycare), 4 times it was pretty serious. Because of that I'm sure he regressed a little, but at the same time we weren't comfortable leaving him knowing he had a fever or was suffering. Also, is it even possible to sleep train for a wakeup that early in the morning? Will it teach him to sleep in? Or will it just mean 3 hours of crying every morning?