Here's another detail of note. The OP's quilt (which I believe is a Rail Fence variation) doesn't truly represent the Nazi swastika. Look at the example in the article and notice the center. It is a sleek cross. The quilt we are discussing has the correct "arms," but the center is "nested," which is completely different from the Nazi swastika. Feline Fanatic has pointed out the 5 x 5 vs. 6 x 6 layout difference, which creates the sleek vs. nested center.
I have also heard (but never researched) that the symbol we know as the swastika has ancient origins, most of them peaceful.
I hope your family can enjoy this treasure. I also agree that making a label for it would probably be wise.
Darren