feline fanatic

I agree. It looks to me like the quilt top was folded up for storage and those darn (and I really would use a worse word than that!) varments chewed away right on the folds. That is why the holes are lined up like they are. Don't ask me how I know so well what damage from mice looks like. You would think someone with as many cats as I do would have no experience with that. But I keep my sewing rooms shut off from the cats and rooms that don't get frequented every day in a 100 year old house, well, mice find a way. Can't stand the little beasties.

Anyway, if Prism and I are correct in our assumption of mouse damage, that may be good news. The fabric may not be as fragile as everyone is assuming. I would swap out the damaged sashing pieces with a blue as close as I could get. The butterfly blocks you have a few choices. I think I would put them on to another piece of muslin (the whole block). And reinforce the hole area with either quilting or maybe a fusible in between the original background and the new backing. Then sandwich and quilt it. You could also just cut out the butterfly from the worst damaged blocks and re-applique them on to new background fabric.

another option is how many family members would want a piece of grandma's quilt? If many, maybe just cut it apart and quilt each block as a gift for each member sacrificing the worst chewed ones.