The 13 year old Natasha runs in-- and this has to be one of the most spectacular entrances in fiction. What strikes me especially is that, veer razor-close as he may, Tolstoy never once falls into sentimentality. I am only on page 40 and quite stunned at his ability to render vividly such very different characters as, say, Anna Scherer and Natasha.
As for that 1956 movie, to play Natasha, who could have been more simply perfect than Audrey Hepburn? (Though as she's pictured on the movie poster, she's a bit older than thirteen.)