My opinion is to leave it there. It was their sentiment 'at the time of signing the blocks'. If a person had to make changes to a quilt every time there was a change in life's scene, it would be dramatic. And if it's your gift, it doesn't need the recipients approval. Am sure they aren't going to 'throw it out' or 'not use it' just because that block is in there. If they do, they weren't worthy of the gift in the first place. That's blunt, but IMHO.