User blog comment:Darkcloud1111/Official "The Sea of Monsters (movie)" Discussion/@comment-5593616-20130628195721/@comment-3146930-20130713211806

Simple, even if they are only twelve in the books, how they actually look really depends on the mind of the reader. I can picture the fights in my head how I want, so if in my mind Percy or Annabeth look older, stronger, less like a twelve year old, then obviously reading the books becomes really simple.