The best way to travel with three kids?

I spend a little of each day thinking and planning for our trip over seas. It's becoming an obsession. Our travel guide, Pam Little, sends frequent updates that keep me on the edge of my seat. Today's email included details of our time in Sydney, Australia. I am so excited that I'd like to pack NOW. But, I am a little anxious too. Being a planner, I keep making and revising my lists. The "simple" task of packing for the children keeps me awake at night. We can take one, yes, that's means only ONE, suitcase per person that weighs no more than 44 pounds. We will be traveling for three months and in varying environments/climates. So, which shoes will provide the most comfort and versatility. The suggestion is to take one dress for three dress-up occasions. Which one? The kiddos will need "activities" along with their school work to keep them busy. Which ones will sustain their interests the longest? What hygiene items do I take and which ones can I get upon arrival? (I hear their shampoo is outrageously priced?) Which meds do I take? And so on . . . I can make myself sick with worry . . . So, I am praying DAILY that I will be flexible as we travel, that we'll be safe, and that we'll stay healthy. (Oh, and if possible, God, please let me remember everything on my list!) If any of you have traveled overseas with little ones and have suggestions for a smooth journey, send them my way! :)