Jason Waking Up at night...

A question for the mommies and daddies out there...

Jason (3 years old) has started waking up at 2-3 in the morning, rocking and in general in a good mood, or calling out for our attention. This has happened some times after we take him across time zones. We did this twice in November, and while I don't know for certain that this contributes to the current explosion of nocturnal activity, I have to wonder. It's devastating to our sleep patterns right now, and I was wondering if any of you have suggestions for helping a child sleep through the night, or any helpful observations or questions?