My bad experience was i brought my elder daughter to Japan when she was 3 yrs but she then got high fever .....and then cramped on the street (while we are shopping in the shopping mall)... wow...then we can police and then back to hotel and call insurance company ....and to the hospital.... for injection.....luckily, it was the last day of trip ....and then we took a flight back to HK, but i never be able to eat and sleep any during the 4 hrs flight cos she still have high fever.....finally when she arrived hk, she was totally get well....this is my story...so my ex-hubby not willing to bring the kids to travel due to this bad memory while they are too young.. but luckily i brought all the mechines (fever relief, cough.. cold.etc) with me, while we are in hospital, show the daughter and she gave us similar medicine.. and i told her can call her family doctor if she need so. hehe. so when u guys bring little kids to travel, can consider this method ar....