I carried three and with 12 years between lots of different carriers were popular over that time. Anything front pack is heavy after 12 pounds. I have had
A snuggle
Padded ring sling
Not padded ring slings with lots of extra fabric
Framed back pack
Mai tai
A moby wrap
A pouch sling sew by a friend out of beautiful raw hemp blend fabric, but it sagged way to much and had to be altered I would say from that experience that knitted fabric would be to stretchy
And even cotton gives under weight,
Felting would be to hot in most climates against a body. And felted ties to hard to tie do to thickness.
There are so many beautiful knitted thing for babies, maybe a carrier is on thing to get sewn for you ( lot of work from home moms sell custom items) and maybe you could trade for knit baby pants or soakers
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