I have repaired a quilt like this before using tulle, a very fine mesh netting in a neutral color. Believe it or not it won't show. You need to have something to fill in the holes though. Tulle can cover the tears and you can stitch down the edges of the tears through the tulle then cut the excess off. I would do the best you could to repair the spots you can, and then only display it, not wrap up in it. That is if you want it to be around. But know that the best complement you can give a quiltmaker is to use it up and wear it out. Your mom would be pleased to know it gave you and your sister joy.