Elizabeth relates how she came to join the Frankenstein household:
Madame Moritz, her mother, was a widow with four children, of whom Justine was the third. This girl had always been the favourite of her father; but, through a strange perversity, her mother could not endure her, and, after the death of M. Moritz, treated her very ill. My aunt observed this; and, when Justine was twelve years of age, prevailed on her mother to allow her to live at her house. (1.5.3)Justine became a favorite of both Victor and his mother, and from them received an education.
She is accused of the murder of William (1.6.10), is convicted on circumstantial evidence (1.7.5), and, although thought innocent by the entire Frankenstein family, is executed for the crime (1.7.10-2.1.1).