Hello my daughter is nearly 8 and i’ve always been taught by my endo that if in doubt give the extra dose as it will do less harm than not giving it when we travelled to America (from England) we had a letter from the doctor explaining emergency procedures for her but we also had another letter for Customs stating that the needles and paraphanalia were emergency medical equipment and that I was not a drug dealer!!! saved a lot of undignified probing seeing as I always carry it in my handbag which gets x rayed!! Hope this helps, by the way as it happens even with the change in water and diet she didn’t get an upset stomach at all and managed to ride the tower of terror at Disney without any side effects!!!!