David's mother died when he was five years old, leaving David with his father and his father's sister, Ellen. David seems to have no memories of her, and he imagines her as a gross corpse that haunts him. Whereas his father rarely speaks of her, Ellen speaks of her often and praises her in extreme terms that make David feel unworthy of being her son.
Once, when David told his father and Ellen that he had a nightmare about his mother, "They concluded that the death of my mother had had this unsettling effect on my imagination and perhaps they thought that I was grieving for her. And I may have been, but if that is so, then I am grieving still" (1.1.24).