Natasha concluded that she must be on the chest in the passage.

The chest in the passage was the place of mourning for the younger female generation in the Rostov household.

And there in fact was Sonya lying face downward on Nurse's dirty feather bed on the top of the chest, crumpling her gauzy pink dress under her, hiding her face with her slender fingers, and sobbing so convulsively that her bare little shoulders shook.