cell w children." ♪ like a dr. jekyll and mr. hyde, herr fritzl always made sure to celebrate birthdays and holidays with his cellar family, even bringing down a christmas tree. >> translator: we know today from the doctors that those who are imprisoned do things that are totally at a different pace, the way they talk, the way they now choose to spend their time in freedom. it's simply impossible to imagine what it must have been like to establish a daily routine in this prison and to live with the constant reminder of the world outside, watching television, seeing pictures, and hearing stories from their father about what life was like up there. >> meanwhile, elisabeth tried to give her imprisoned children a degree of normality, teaching them to read and write. >> they had lessons. they learned grammar.