I believe that the young Anastasia escaped at the time of the assasination of her father, mother, and her older siblings. After watching the specials on her, I feel confident that she did survive the overthrow. I also believe that if she hasn't already died she is still out there. And it would be a huge miracle for her to come out. She may be able to take the throne foe her father because I believe that is what he would of wanted her to do.