mamaof4, I completely agree! Ergos are the best! I currently use a moby wrap with dck's just because I got rid of my ergo when my son was older. I like the moby too, but ergos are the best, imo. You can have them in these 'til they're 2 or 3 theoretically, but for the purposes of soothing and daycare in general, I am thinking not much longer than 18 months? After that, they normally want to walk. If the weight is dispersed properly, and you're using the carrier correctly, there shouldn't be a lot of strain on your back. Wraps and the ergo are different than those snugli things.