Did it last year with our 3 year old!
1) check in as early as poss to get best (and possibly spare) seats on 1st/onward flight
2) On the recommendation of a friend with 3 who had also done the flight, we bought a portable DVD player. It was PRICELESS!
3) Wrap little gifts up to keep them entertained
4) Stop for a few hours in Singapore. Lots to see & do (cinema, playgrounds, butterfly gardens, pool, foot massage, Internet access: ALL FOR FREE). Have a shower and you'll feel human enough to do the second flight!
5) rescue remedy
6) Gin (or valium
Good luck!
I'm flying with DS in November...
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