Maybe just tell your sister that there are lots of books out there trying to discredit the Bible....don't believe them.
Then tell her if she really wants to know the truth herself, start reading the Bible and you GUARANTEE that God will reveal His true words, if she is truly sincere.
Thanks all. I read those old discussions about it and found that it is so easy to bunk its not even funny. I read tons and tons of books; but my sister is one of those types that read very little, so that when she does she really gets sucked in to whatever nonsense it is. I really should read it, but I have a reading list with too many other juicy stuff to read.