She doesn't have to quilt anything on it. She can write whatever she things is appropriate onto the square of fabric such as a poem or words of wisdom. As I read it, someone else will be making it into a quilt to use in the wedding ceremony. If you have some Freezer paper, iron it to the back and make sure that none of her writing goes anywhere close to the edges. Use a Micron archival permanent pen that is available at JAF.