Importance of Attic?

Alicia is fascinated with the attic. Olivia sends her up there late in her pregnancy to explore, hoping she will fall and lose the baby. Later, Olivia tries to sneak through the attic to catch Malcolm visiting Alicia in the secluded second story room during her second pregnancy, but becomes lost in the dark. Olivia is so frightened she will never again set foot in the attic.