One wag has noted that Camelbak represents one of the most successful marketing efforts in history, having convinced millions of people that a $75 聯hydration pack” is superior to an $8 Nalgene bottle.
Ultimate Direction Teocalli

I聮m pretty ambivalent about Camelbaks and other bladder-based watering systems (what a funny phrase: 聯bladder-based”). I use one occasionally on mountain-biking trips when a couple of water bottles on the bike frame aren聮t enough (plus my dualie has practical space for only one bottle). That way I can carry fluids plus a jacket and lunch. Once in a while I聮ll use a bladder with a backpack, but I聮m usually happier with a water bottle. I just like the ritual of stopping, taking off the pack, flopping on the ground, and having a nice drink. Sipping through a tube while marching along makes it all seem too much like I聮m racing in The Raid (www.theraid.org) or something.
That said, a pretty good hike/bike hydration pack is the Ultimate Direction Teocalli ($100; www.ultimatedirection.com), which can be configured to carry about 600 cubic inches of gear聴barely enough for a minimalist day hike, but it聮s something. Camelbak聮s H.A.W.G. ($100; www.camelbak.com) has a little more capacity, although you risk too big a load to bicycle comfortably. But it聮s the better choice for day-hiking. The North Face聮s Megamouth ($95; www.thenorthface.com) is a little larger yet (1,100 cubic inches).
I simply wouldn聮t recommend a hydration pack for youngsters. I think trying to manage a bike is challenging enough, without giving a child something else to do, like trying to get a drink while riding. In any event, I just can聮t imagine a trip that聮s arduous enough for an 8-year-old to require constant fluid replenishment. A water bottle in a small daypack聴better yet, in dad聮s pack!聴should be fine for nearly any outing.
Get more advice from the Gear Guy as he picks this season聮s top gifts in You聮ll probably find a few things to put on your own wish list, too.