Imho a dense meander would be best as well - esp if you are good at meandering on the domestic or have a longarm. Another option is to echo her seams as quilting - stitching 1/4" away from all her seams on each side through the batting and backing. It would provide stability for the seam and there would be little or no pressure on the seam when pulled. This would take time, but once you got it stabilized she might be able the help quilt it!!
I am sure you are proud of her efforts. Hoe you share her quilt when it is complete!