In reply to Hatty:
I have three children, now teenagers. I carried them all into toddlerhood with varying degrees of success.
Eldest, I had a soft carrier on my chest until she outgrew it at six months, when I got a Kelty Kids framed backpack. It was well-made and secure, but, as with one of the above posters, she soon got too heavy and awkward for me to lift onto my back on my own and I had to use props. Then I got pregnant with no 2 so couldn’t fasten it round my waist.
Whilst it was a sturdy pack, it weighed a lot, wasn’t particularly comfortable for me or my husband (we are at opposite ends of height range), and because child is held away from parents body, it’s easy for them to get cold without being noticed.
Child no 2, I was determined to be able to carry her for longer so entered into the world of baby-wearing. Tried a few different slings and found for older babies/toddlers, either a wrap style sling (long length of fabric) or a mei-tai, similar to the Connecta mentioned above, worked well. Both are very adjustable, to child and adult size, lightweight, can be tied in different ways to suit circumstances and carries the child close to the body, which is great for temperature regulation and centre of gravity. I could also get them on and off without assistance which was a huge bonus.
They do have a steeper learning curve than the framed packs, especially the wraps but I found it worthwhile to learn new techniques and carried child no 2 until she was just over two years old and no 3 until she was about 18 months (she was an extremely independent person who wanted to walk everywhere).