nook works fine with its official site pulished books, but this is not equal to the kindle readers. Kindle has its exclusive book storefront the same, amazon provides books that suit kindle reading perfectly. I am afraid you cannot share the books you bought from barns&noble shop directly with your mom. but things alawys got the corresponding solution.just make use of a software to convert nook epub book format to kindle supported azw one, then it can be possible for you two to share books all the time. you can search this software "epubsoft ebook converter".
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