I have exactly the same pack (Kelty Back country) and I still carry my daughter (4 years old and 30+ lbs) every now and then. It isn't bad as the sholder straps and waist belt are great. Usually my 2 year old gets preference with the carrier though.

That said, my wife wouldn't want to carry our 4 year old daughter in it.

We use ours all the time and took our 1 year old on a 3 day backpacking trip with it a few years ago. She had a great time. My wife carried our 1 year old and I carried the pack (with all the dirty diapers).
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Without a doubt, the hardest thing of all in a survival situation is to cook without the benefit of seasonings and flavourings. - Ray Mears

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