My had a 2nd generation kindle that was registered to an account under her name and purchased and received books to it. Since then we decided to buy our products from my account and I replaced her 2nd generation with a paper white. Now we have books on two accounts but the paper white is only registered to my account. Is there a way to have the same paper white registered to 2 accounts? I don't see a way to do it. Looks like I have to deregister it first.