She is supremely unintelligent, and completely unreliable. She is devoted to her "Ducky-boos," as she calls Duckula, and has a deep maternal affection for him, although her clumsiness often inadvertently causes him harm. A recurring gag is her inability to understand what people around her are talking about. She often mixes up words and takes insult at conversations not directed at her. She is very ditzy and motherly, sometimes hugging Duckula so tightly she nearly suffocates him. In "Dr Goosewing and Mr Duck" when she accidentally drinks the carpet stain removal liquid created by Goosewing she becomes extremely intelligent.Like Igor, her age is uncertain, although she has apparently been with the Duckula family for several incarnations.
In the episode "Igor's Busy Day," Igor recalls Duckula's great-grandfather, who used to allow stranded travellers to stay the night. Nanny concurs that she remembers those days, possibly indicating she also has a very long lifespan. Her right arm is perpetually in a sling, (though it is revealed in a newspaper comic that she, in fact, is only wearing the sling to cover up a tattoo). The sling itself seems to have unlimited carrying capacity, as she is able to produce any number of items from it, in the style of Harpo Marx's recurring magic satchel joke.