When Walter glanced back to check on her, a terrible sorrow washed through him. Sorrow for Ida; for her strangeness, or the strangeness that had been visited upon her. Sorrow for himself, too. He supposed it might be self-pity, though what it really felt like was grief, for if Ida truly had come to the end of her unnaturally long childhood, it meant he, Walter, was about to lose a burden that had long since been transformed into devotion.
