I too think this quilt should be used by your daughter albeit tenderly. What I mean by that is let her lay on it or under it in her room or in the house but don't let it be dragged around. It would even be a great lesson for her in caring for old family objects. Yes, your granny would love this idea I think. It appears from the photo that those hexagons in the sort of purple color are the only ones falling apart? If so, I would try to find some fabric in that color family (maybe repro fabric?) and applique new hexagons right on top of the old. I did this for a friend many years ago. I found a pale yellow that matched the worn patches very closely. It turned out quite well although they did not use the quilt anymore but just folded up up at the end of their bed. Good luck with whatever you decide. Afterall, it is your quilt to do with as you please.