Jetlag sucks

i'm lucky enough to never suffer from jetlag, but my sister suffers from it the entire time we're abroad. everytime we go to hong kong (12-13hour plane trip, and 7-8 hours ahead of our time zone) she ends up sleeping during the day and staying up until morning watching tv because she just can't get used to it. though it means when we get back to england she doesn't have any jetlag.

only once did she not suffer from it i think, when we went to singapore for about 3 days (again flying from england) since we arrived in the morning around 10-ish, we went on a load of trips till 6-ish and which point we were all completely knackered and went to sleep later that evening fine. and since our next two stops were australia and hong kong, she didn't get any jetlag (time difference between singapore/hong kong and australia is only about 1-2 hours)

Jam it back in, in the dark.