Typically kids get over jetlag quicker than adults. I've had the jetlag thing with 2 kids under two and it's not a lot of fun for a day, but gets better fast.
The tips are basically the same as for an adult:
- Try to get on destination time as fast as possible.
- Extra naps and longer sleep. But do try to adjust hours as fast as possible.
- Extra fluids.
- Lots of TLC.
- No big adventures. Peace and quiet.
Extra tip for kids:
- "Easy foods" that baby is comfortable with.
- Ensure familiar toys are around.
- Be patient with whining.
Lots of outdoors/sunshine time during the day. Blackout curtains on the windows. Extra fluids and/or juice popsicles. More fibre in his diet...prunes, whole wheat flour, bran cereal. Loads of patience...it's not their fault that they're feeling discombobulated!
In any case it should only take a couple of days for 95% of the effects to be over. Any longer than that and you're not "curing" aggressively enough.
I have met adults who haven't adjusted after 6-7 days. They always wondered how I managed two week long trips a month from New York to London without killing myself.
Ruth's tricks are sound. Give the body clues as to when it's day and when it's night.