hi
we have been a couple of times with dd who is 3.

I always take red cordial, - it apparantly kills any bugs in the tummy.

I also take kids stuff to stop the runs and gastrolite to keep them hydrated in case of vomiting or diarrohea.

When she was 3 she enjoyed a portable dvd to watch her favourtie dvd's which provided great distraction when eating out at dinner.

Also took books and colouring stuff to keep her entertained on the plane and anywhere else.

Have a great time. The Balinese love kids and are so friendly.