If it were me, and for the sentimental value. I would take off all the sashing. Then carefully iron the butterflys out. Then, I would stabilize the Fabric the butterflys are on with a medium weight stabilizer. I would then, put on a new borders in the color that matches the original color. And, then have it quilted. Even with all the age and wear, it will be a beautiful quilt. And, a beautiful memory of your DGM.