If you are including a lengthy hike in your possible scenarios, you should explore the techniques developed by thru hiker, the sort of folk who do the length of the Appalachian Trail, the Continental Divide Trail, or the pacific Crest Trail. Such walkers typically cover 20-30 miles a day, resupplying at intervals of about one week. Their gear is streamlined, multi-use, and extraordinarily light. They also are in very good physical condition,so keep hiking - that will be tremendously important.

Hopefully none of this will ever be necessary, but if it does come to pass, let's hope your daughter is closer to sixteen than to six, so she can say, "Gosh, Mom, you look tired - let me carry your pack for a while."