What is Afoot in the Household?

Childhood is really a bunch of phases strung together.  Some are good, some are not so good and all must come to an end.  I always tell this to myself when we are in a particularly nasty phase.  Poop in pants, super sloppy eating, running away from mom like it is a game, all of those lovely things.  However, the one phase that seems to be a recurring theme in our household are sleep issues.  We have had them since, dare I say Day One?  If not Day One, it must have been by 12 weeks when I went back to work and Jac got his first cold while meeting his teachers - three days BEFORE he started daycare. 

Since then we have had it all, you name it.  Nightmares, night terrors, bed wetting, sleep walking, teeth grinding, throwing up in the middle of the night, trouble going to sleep, trouble staying asleep, kids joining us in bed, us joining kids in their beds, throw in the random ear infection and it is a wonder Jeff and I aren't walking zombies.  Jeff seems to have adapted.  We have a rough night and the next day he gets up, gets ready and goes to work.  Like nothing happened.  He might take a nap on the weekend, but I am pretty sure he has always napped on the weekend.  I however, have not adapted.  I get crabbier and crabbier as the saga continues.  Surely this too must pass? 

So currently we are going through a phase where Jac is waking up again in the middle of the night.  The problem is that when he wakes up, for some reason Mia is waking up also and then we have two kids awake in the middle of the night.  Jac normally goes back to sleep either in bed with us, or me in bed with him in about 10 minutes.  Mia on the other hand, once disturbed she may take up to two hours to get back to sleep, ouch.  Why is he waking?  I have no idea.  His diet is great, he is getting a lot of exercise, our routine is pretty solid, he isn't have nightmares, terrors or falling out of bed.  His teeth grinding seems to have stopped.  So what is the deal?  What gives?  He is restless for no apparant reason.  He is stressed about something, would be my best guess.  He does start Kindergarten in less than two weeks, this is big and more than likely the reason for his angst. 

I really am not sure what to do, if anything.  Continue our routine of course, continue to feed and water well and get plenty of exercise.  And then after that, how do we help our five year deal with stress?  If anyone has any bright ideas, let me know!