I put a ruffle on a baby quilt one time. I regretted doing that in short order. I did the ruffle by hand on the bias by folding over the fabric, pressing it so there was less movement. then using the logest stitch on my machine pulled one thread, the bottom thread, until I had the ruffle I wanted. I then sewed over with a regular stitch,
The ruffle can be problematic putting on the quilt but moreover it is problematic for parent and child.