Is this fabric only in the backing?? Is the front of the quilt in good shape? If so you can put a second back on it, quilt it very lightly just to hold it together and rebind. Leave the "bad" on, don't un-sew it, just add the new back.
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My newest Grandson, Caleb Austin, was born May 29th. I am now Grandma to 4 precious babies. I am so blessed!!!!