I started taking my boys (twins - now 10) on long day hikes when they were barely 3. We would walk for an hour or so and then have a snack. Then, walk a while longer and maybe they would take a nap (on the fleeces that I carried for them). And so on. We covered a lot of ground and they loved getting far out into the woods. By the time they turned 5 they were quite the little hikers and we started going on overnights (with me carrying the gear). At 6 they started carrying small backpacks and now that they are 10 they carry their own gear and a little bit of the group gear. And they're two of the strongest backpackers I know. We have been places together that most of my adult friends would not attempt. We always kept/keep a positive attitude while we backpack along so they've never hiked with anyone that complained of how hard it was or how long it took. Consequently, the boys have positive can do attitudes, really love to backpack, and are a joy to hike with. And we're jusyt getting started. May your experiences be as wonderful as mine have been/are.
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i really don't think that applies to me.