For a similair request from my "neice", I used an extremely thin, featherweight batting and instead of making a completed quilt, I actually made the lightweight quilt into a Duvet Cover. (The backing of the quilt top becomes the fabric pocket for the duvet.) Quilted, Super "thick" once the Quilted Duvet Cover was in place on her duvet, and smiles for all.
Good luck with whatever you work out. I'm sure your daughter will love it.