She should be in a frogged position with her spine in a C curve.
I'd try the ring sling again and try making different adjustments, like tightening each rail in the direction of the fabric, making a snug fit. I find it's easier to get a more comfortable positioning with a ring sling compared to a ERGO at that age. This is b/c her legs can come out the bottom a bit in the chest-to-chest position, making positioning a little easier. Also, try rolling a washcloth or some fabric on the top rail to create a little bumper/headrest. I find it really helps with the fit sometimes.
I think the ERGO really shines with older children and without the insert. It just makes more things to adjust and maneuver.
Teach your children about the global water crisis
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